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2016-08-16x86/syscalls/64: Add compat_sys_keyctl for 32-bit userspaceDavid Howells1-1/+1
commit f7d665627e103e82d34306c7d3f6f46f387c0d8b upstream. x86_64 needs to use compat_sys_keyctl for 32-bit userspace rather than calling sys_keyctl(). The latter will work in a lot of cases, thereby hiding the issue. Reported-by: Stephan Mueller <smueller@chronox.de> Tested-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: David Howells <dhowells@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: keyrings@vger.kernel.org Cc: linux-security-module@vger.kernel.org Link: http://lkml.kernel.org/r/146961615805.14395.5581949237156769439.stgit@warthog.procyon.org.uk Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-16x86/mm/pat: Fix BUG_ON() in mmap_mem() on QEMU/i386Toshi Kani1-19/+0
commit 1886297ce0c8d563a08c8a8c4c0b97743e06cd37 upstream. The following BUG_ON() crash was reported on QEMU/i386: kernel BUG at arch/x86/mm/physaddr.c:79! Call Trace: phys_mem_access_prot_allowed mmap_mem ? mmap_region mmap_region do_mmap vm_mmap_pgoff SyS_mmap_pgoff do_int80_syscall_32 entry_INT80_32 after commit: edfe63ec97ed ("x86/mtrr: Fix Xorg crashes in Qemu sessions") PAT is now set to disabled state when MTRRs are disabled. Thus, reactivating the __pa(high_memory) check in phys_mem_access_prot_allowed(). When CONFIG_DEBUG_VIRTUAL is set, __pa() calls __phys_addr(), which in turn calls slow_virt_to_phys() for 'high_memory'. Because 'high_memory' is set to (the max direct mapped virt addr + 1), it is not a valid virtual address. Hence, slow_virt_to_phys() returns 0 and hit the BUG_ON. Using __pa_nodebug() instead of __pa() will fix this BUG_ON. However, this code block, originally written for Pentiums and earlier, is no longer adequate since a 32-bit Xen guest has MTRRs disabled and supports ZONE_HIGHMEM. In this setup, this code sets UC attribute for accessing RAM in high memory range. Delete this code block as it has been unused for a long time. Reported-by: kernel test robot <ying.huang@linux.intel.com> Reviewed-by: Borislav Petkov <bp@suse.de> Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/1460403360-25441-1-git-send-email-toshi.kani@hpe.com Link: https://lkml.org/lkml/2016/4/1/608 Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-16x86/xen, pat: Remove PAT table init code from XenToshi Kani3-11/+1
commit 88ba281108ed0c25c9d292b48bd3f272fcb90dd0 upstream. Xen supports PAT without MTRRs for its guests. In order to enable WC attribute, it was necessary for xen_start_kernel() to call pat_init_cache_modes() to update PAT table before starting guest kernel. Now that the kernel initializes PAT table to the BIOS handoff state when MTRR is disabled, this Xen-specific PAT init code is no longer necessary. Delete it from xen_start_kernel(). Also change __init_cache_modes() to a static function since PAT table should not be tweaked by other modules. Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Juergen Gross <jgross@suse.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bp@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Toshi Kani <toshi.kani@hp.com> Cc: elliott@hpe.com Cc: paul.gortmaker@windriver.com Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/1458769323-24491-7-git-send-email-toshi.kani@hpe.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-16x86/mtrr: Fix PAT init handling when MTRR is disabledToshi Kani3-10/+18
commit ad025a73f0e9344ac73ffe1b74c184033e08e7d5 upstream. get_mtrr_state() calls pat_init() on BSP even if MTRR is disabled. This results in calling pat_init() on BSP only since APs do not call pat_init() when MTRR is disabled. This inconsistency between BSP and APs leads to undefined behavior. Make BSP's calling condition to pat_init() consistent with AP's, mtrr_ap_init() and mtrr_aps_init(). Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bp@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Toshi Kani <toshi.kani@hp.com> Cc: elliott@hpe.com Cc: konrad.wilk@oracle.com Cc: paul.gortmaker@windriver.com Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/1458769323-24491-6-git-send-email-toshi.kani@hpe.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-16x86/mtrr: Fix Xorg crashes in Qemu sessionsToshi Kani2-2/+14
commit edfe63ec97ed8d4496225f7ba54c9ce4207c5431 upstream. A Xorg failure on qemu32 was reported as a regression [1] caused by commit 9cd25aac1f44 ("x86/mm/pat: Emulate PAT when it is disabled"). This patch fixes the Xorg crash. Negative effects of this regression were the following two failures [2] in Xorg on QEMU with QEMU CPU model "qemu32" (-cpu qemu32), which were triggered by the fact that its virtual CPU does not support MTRRs. #1. copy_process() failed in the check in reserve_pfn_range() copy_process copy_mm dup_mm dup_mmap copy_page_range track_pfn_copy reserve_pfn_range A WC map request was tracked as WC in memtype, which set a PTE as UC (pgprot) per __cachemode2pte_tbl[]. This led to this error in reserve_pfn_range() called from track_pfn_copy(), which obtained a pgprot from a PTE. It converts pgprot to page_cache_mode, which does not necessarily result in the original page_cache_mode since __cachemode2pte_tbl[] redirects multiple types to UC. #2. error path in copy_process() then hit WARN_ON_ONCE in untrack_pfn(). x86/PAT: Xorg:509 map pfn expected mapping type uncached- minus for [mem 0xfd000000-0xfdffffff], got write-combining Call Trace: dump_stack warn_slowpath_common ? untrack_pfn ? untrack_pfn warn_slowpath_null untrack_pfn ? __kunmap_atomic unmap_single_vma ? pagevec_move_tail_fn unmap_vmas exit_mmap mmput copy_process.part.47 _do_fork SyS_clone do_syscall_32_irqs_on entry_INT80_32 These negative effects are caused by two separate bugs, but they can be addressed in separate patches. Fixing the pat_init() issue described below addresses the root cause, and avoids Xorg to hit these cases. When the CPU does not support MTRRs, MTRR does not call pat_init(), which leaves PAT enabled without initializing PAT. This pat_init() issue is a long-standing issue, but manifested as issue #1 (and then hit issue #2) with the above-mentioned commit because the memtype now tracks cache attribute with 'page_cache_mode'. This pat_init() issue existed before the commit, but we used pgprot in memtype. Hence, we did not have issue #1 before. But WC request resulted in WT in effect because WC pgrot is actually WT when PAT is not initialized. This is not how it was designed to work. When PAT is set to disable properly, WC is converted to UC. The use of WT can result in a system crash if the target range does not support WT. Fortunately, nobody ran into such issue before. To fix this pat_init() issue, PAT code has been enhanced to provide pat_disable() interface. Call this interface when MTRRs are disabled. By setting PAT to disable properly, PAT bypasses the memtype check, and avoids issue #1. [1]: https://lkml.org/lkml/2016/3/3/828 [2]: https://lkml.org/lkml/2016/3/4/775 Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bp@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Toshi Kani <toshi.kani@hp.com> Cc: elliott@hpe.com Cc: konrad.wilk@oracle.com Cc: paul.gortmaker@windriver.com Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/1458769323-24491-5-git-send-email-toshi.kani@hpe.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-16x86/mm/pat: Replace cpu_has_pat with boot_cpu_has()Toshi Kani1-2/+2
commit d63dcf49cf5ae5605f4d14229e3888e104f294b1 upstream. Borislav Petkov suggested: > Please use on init paths boot_cpu_has(X86_FEATURE_PAT) and on fast > paths static_cpu_has(X86_FEATURE_PAT). No more of that cpu_has_XXX > ugliness. Replace the use of cpu_has_pat on init paths with boot_cpu_has(). Suggested-by: Borislav Petkov <bp@suse.de> Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Robert Elliott <elliott@hpe.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: konrad.wilk@oracle.com Cc: paul.gortmaker@windriver.com Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/1458769323-24491-4-git-send-email-toshi.kani@hpe.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-16x86/mm/pat: Add pat_disable() interfaceToshi Kani2-1/+13
commit 224bb1e5d67ba0f2872c98002d6a6f991ac6fd4a upstream. In preparation for fixing a regression caused by: 9cd25aac1f44 ("x86/mm/pat: Emulate PAT when it is disabled") ... PAT needs to provide an interface that prevents the OS from initializing the PAT MSR. PAT MSR initialization must be done on all CPUs using the specific sequence of operations defined in the Intel SDM. This requires MTRRs to be enabled since pat_init() is called as part of MTRR init from mtrr_rendezvous_handler(). Make pat_disable() as the interface that prevents the OS from initializing the PAT MSR. MTRR will call this interface when it cannot provide the SDM-defined sequence to initialize PAT. This also assures that pat_disable() called from pat_bsp_init() will set the PAT table properly when CPU does not support PAT. Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bp@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Robert Elliott <elliott@hpe.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: konrad.wilk@oracle.com Cc: paul.gortmaker@windriver.com Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/1458769323-24491-3-git-send-email-toshi.kani@hpe.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-16x86/mm/pat: Add support of non-default PAT MSR settingToshi Kani3-22/+55
commit 02f037d641dc6672be5cfe7875a48ab99b95b154 upstream. In preparation for fixing a regression caused by: 9cd25aac1f44 ("x86/mm/pat: Emulate PAT when it is disabled")' ... PAT needs to support a case that PAT MSR is initialized with a non-default value. When pat_init() is called and PAT is disabled, it initializes the PAT table with the BIOS default value. Xen, however, sets PAT MSR with a non-default value to enable WC. This causes inconsistency between the PAT table and PAT MSR when PAT is set to disable on Xen. Change pat_init() to handle the PAT disable cases properly. Add init_cache_modes() to handle two cases when PAT is set to disable. 1. CPU supports PAT: Set PAT table to be consistent with PAT MSR. 2. CPU does not support PAT: Set PAT table to be consistent with PWT and PCD bits in a PTE. Note, __init_cache_modes(), renamed from pat_init_cache_modes(), will be changed to a static function in a later patch. Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bp@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Toshi Kani <toshi.kani@hp.com> Cc: elliott@hpe.com Cc: konrad.wilk@oracle.com Cc: paul.gortmaker@windriver.com Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/1458769323-24491-2-git-send-email-toshi.kani@hpe.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-16x86/mm/32: Enable full randomization on i386 and X86_32Hector Marco-Gisbert1-13/+1
commit 8b8addf891de8a00e4d39fc32f93f7c5eb8feceb upstream. Currently on i386 and on X86_64 when emulating X86_32 in legacy mode, only the stack and the executable are randomized but not other mmapped files (libraries, vDSO, etc.). This patch enables randomization for the libraries, vDSO and mmap requests on i386 and in X86_32 in legacy mode. By default on i386 there are 8 bits for the randomization of the libraries, vDSO and mmaps which only uses 1MB of VA. This patch preserves the original randomness, using 1MB of VA out of 3GB or 4GB. We think that 1MB out of 3GB is not a big cost for having the ASLR. The first obvious security benefit is that all objects are randomized (not only the stack and the executable) in legacy mode which highly increases the ASLR effectiveness, otherwise the attackers may use these non-randomized areas. But also sensitive setuid/setgid applications are more secure because currently, attackers can disable the randomization of these applications by setting the ulimit stack to "unlimited". This is a very old and widely known trick to disable the ASLR in i386 which has been allowed for too long. Another trick used to disable the ASLR was to set the ADDR_NO_RANDOMIZE personality flag, but fortunately this doesn't work on setuid/setgid applications because there is security checks which clear Security-relevant flags. This patch always randomizes the mmap_legacy_base address, removing the possibility to disable the ASLR by setting the stack to "unlimited". Signed-off-by: Hector Marco-Gisbert <hecmargi@upv.es> Acked-by: Ismael Ripoll Ripoll <iripoll@upv.es> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: akpm@linux-foundation.org Cc: kees Cook <keescook@chromium.org> Link: http://lkml.kernel.org/r/1457639460-5242-1-git-send-email-hecmargi@upv.es Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Laura Abbott <labbott@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-10perf/x86: fix PEBS issues on Intel Atom/Core2Stephane Eranian1-1/+8
commit 1424a09a9e1839285e948d4ea9fdfca26c9a2086 upstream. This patch fixes broken PEBS support on Intel Atom and Core2 due to wrong pointer arithmetic in intel_pmu_drain_pebs_core(). The get_next_pebs_record_by_bit() was called on PEBS format fmt0 which does not use the pebs_record_nhm layout. Signed-off-by: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: kan.liang@intel.com Fixes: 21509084f999 ("perf/x86/intel: Handle multiple records in the PEBS buffer") Link: http://lkml.kernel.org/r/1449182000-31524-3-git-send-email-eranian@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-10pvclock: Add CPU barriers to get correct version valueMinfei Huang2-0/+6
commit 749d088b8e7f4b9826ede02b9a043e417fa84aa1 upstream. Protocol for the "version" fields is: hypervisor raises it (making it uneven) before it starts updating the fields and raises it again (making it even) when it is done. Thus the guest can make sure the time values it got are consistent by checking the version before and after reading them. Add CPU barries after getting version value just like what function vread_pvclock does, because all of callees in this function is inline. Fixes: 502dfeff239e8313bfbe906ca0a1a6827ac8481b Signed-off-by: Minfei Huang <mnghuan@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-10x86/quirks: Add early quirk to reset Apple AirPort cardLukas Wunner1-0/+64
commit abb2bafd295fe962bbadc329dbfb2146457283ac upstream. The EFI firmware on Macs contains a full-fledged network stack for downloading OS X images from osrecovery.apple.com. Unfortunately on Macs introduced 2011 and 2012, EFI brings up the Broadcom 4331 wireless card on every boot and leaves it enabled even after ExitBootServices has been called. The card continues to assert its IRQ line, causing spurious interrupts if the IRQ is shared. It also corrupts memory by DMAing received packets, allowing for remote code execution over the air. This only stops when a driver is loaded for the wireless card, which may be never if the driver is not installed or blacklisted. The issue seems to be constrained to the Broadcom 4331. Chris Milsted has verified that the newer Broadcom 4360 built into the MacBookPro11,3 (2013/2014) does not exhibit this behaviour. The chances that Apple will ever supply a firmware fix for the older machines appear to be zero. The solution is to reset the card on boot by writing to a reset bit in its mmio space. This must be done as an early quirk and not as a plain vanilla PCI quirk to successfully combat memory corruption by DMAed packets: Matthew Garrett found out in 2012 that the packets are written to EfiBootServicesData memory (http://mjg59.dreamwidth.org/11235.html). This type of memory is made available to the page allocator by efi_free_boot_services(). Plain vanilla PCI quirks run much later, in subsys initcall level. In-between a time window would be open for memory corruption. Random crashes occurring in this time window and attributed to DMAed packets have indeed been observed in the wild by Chris Bainbridge. When Matthew Garrett analyzed the memory corruption issue in 2012, he sought to fix it with a grub quirk which transitions the card to D3hot: http://git.savannah.gnu.org/cgit/grub.git/commit/?id=9d34bb85da56 This approach does not help users with other bootloaders and while it may prevent DMAed packets, it does not cure the spurious interrupts emanating from the card. Unfortunately the card's mmio space is inaccessible in D3hot, so to reset it, we have to undo the effect of Matthew's grub patch and transition the card back to D0. Note that the quirk takes a few shortcuts to reduce the amount of code: The size of BAR 0 and the location of the PM capability is identical on all affected machines and therefore hardcoded. Only the address of BAR 0 differs between models. Also, it is assumed that the BCMA core currently mapped is the 802.11 core. The EFI driver seems to always take care of this. Michael Büsch, Bjorn Helgaas and Matt Fleming contributed feedback towards finding the best solution to this problem. The following should be a comprehensive list of affected models: iMac13,1 2012 21.5" [Root Port 00:1c.3 = 8086:1e16] iMac13,2 2012 27" [Root Port 00:1c.3 = 8086:1e16] Macmini5,1 2011 i5 2.3 GHz [Root Port 00:1c.1 = 8086:1c12] Macmini5,2 2011 i5 2.5 GHz [Root Port 00:1c.1 = 8086:1c12] Macmini5,3 2011 i7 2.0 GHz [Root Port 00:1c.1 = 8086:1c12] Macmini6,1 2012 i5 2.5 GHz [Root Port 00:1c.1 = 8086:1e12] Macmini6,2 2012 i7 2.3 GHz [Root Port 00:1c.1 = 8086:1e12] MacBookPro8,1 2011 13" [Root Port 00:1c.1 = 8086:1c12] MacBookPro8,2 2011 15" [Root Port 00:1c.1 = 8086:1c12] MacBookPro8,3 2011 17" [Root Port 00:1c.1 = 8086:1c12] MacBookPro9,1 2012 15" [Root Port 00:1c.1 = 8086:1e12] MacBookPro9,2 2012 13" [Root Port 00:1c.1 = 8086:1e12] MacBookPro10,1 2012 15" [Root Port 00:1c.1 = 8086:1e12] MacBookPro10,2 2012 13" [Root Port 00:1c.1 = 8086:1e12] For posterity, spurious interrupts caused by the Broadcom 4331 wireless card resulted in splats like this (stacktrace omitted): irq 17: nobody cared (try booting with the "irqpoll" option) handlers: [<ffffffff81374370>] pcie_isr [<ffffffffc0704550>] sdhci_irq [sdhci] threaded [<ffffffffc07013c0>] sdhci_thread_irq [sdhci] [<ffffffffc0a0b960>] azx_interrupt [snd_hda_codec] Disabling IRQ #17 Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=79301 Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=111781 Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=728916 Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=895951#c16 Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1009819 Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1098621 Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1149632#c5 Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1279130 Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1332732 Tested-by: Konstantin Simanov <k.simanov@stlk.ru> # [MacBookPro8,1] Tested-by: Lukas Wunner <lukas@wunner.de> # [MacBookPro9,1] Tested-by: Bryan Paradis <bryan.paradis@gmail.com> # [MacBookPro9,2] Tested-by: Andrew Worsley <amworsley@gmail.com> # [MacBookPro10,1] Tested-by: Chris Bainbridge <chris.bainbridge@gmail.com> # [MacBookPro10,2] Signed-off-by: Lukas Wunner <lukas@wunner.de> Acked-by: Rafał Miłecki <zajec5@gmail.com> Acked-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Andy Lutomirski <luto@kernel.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Chris Milsted <cmilsted@redhat.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Michael Buesch <m@bues.ch> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yinghai Lu <yinghai@kernel.org> Cc: b43-dev@lists.infradead.org Cc: linux-pci@vger.kernel.org Cc: linux-wireless@vger.kernel.org Link: http://lkml.kernel.org/r/48d0972ac82a53d460e5fce77a07b2560db95203.1465690253.git.lukas@wunner.de [ Did minor readability edits. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-10x86/quirks: Reintroduce scanning of secondary busesLukas Wunner1-13/+21
commit 850c321027c2e31d0afc71588974719a4b565550 upstream. We used to scan secondary buses until the following commit that was applied in 2009: 8659c406ade3 ("x86: only scan the root bus in early PCI quirks") which commit constrained early quirks to the root bus only. Its motivation was to prevent application of the nvidia_bugs quirk on secondary buses. We're about to add a quirk to reset the Broadcom 4331 wireless card on 2011/2012 Macs, which is located on a secondary bus behind a PCIe root port. To facilitate that, reintroduce scanning of secondary buses. The commit message of 8659c406ade3 notes that scanning only the root bus "saves quite some unnecessary scanning work". The algorithm used prior to 8659c406ade3 was particularly time consuming because it scanned buses 0 to 31 brute force. To avoid lengthening boot time, employ a recursive strategy which only scans buses that are actually reachable from the root bus. Yinghai Lu pointed out that the secondary bus number read from a bridge's config space may be invalid, in particular a value of 0 would cause an infinite loop. The PCI core goes beyond that and recurses to a child bus only if its bus number is greater than the parent bus number (see pci_scan_bridge()). Since the root bus is numbered 0, this implies that secondary buses may not be 0. Do the same on early scanning. If this algorithm is found to significantly impact boot time or cause infinite loops on broken hardware, it would be possible to limit its recursion depth: The Broadcom 4331 quirk applies at depth 1, all others at depth 0, so the bus need not be scanned deeper than that for now. An alternative approach would be to revert to scanning only the root bus, and apply the Broadcom 4331 quirk to the root ports 8086:1c12, 8086:1e12 and 8086:1e16. Apple always positioned the card behind either of these three ports. The quirk would then check presence of the card in slot 0 below the root port and do its deed. Signed-off-by: Lukas Wunner <lukas@wunner.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yinghai Lu <yinghai@kernel.org> Cc: linux-pci@vger.kernel.org Link: http://lkml.kernel.org/r/f0daa70dac1a9b2483abdb31887173eb6ab77bdf.1465690253.git.lukas@wunner.de Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-10x86/quirks: Apply nvidia_bugs quirk only on root busLukas Wunner1-0/+7
commit 447d29d1d3aed839e74c2401ef63387780ac51ed upstream. Since the following commit: 8659c406ade3 ("x86: only scan the root bus in early PCI quirks") ... early quirks are only applied to devices on the root bus. The motivation was to prevent application of the nvidia_bugs quirk on secondary buses. We're about to reintroduce scanning of secondary buses for a quirk to reset the Broadcom 4331 wireless card on 2011/2012 Macs. To prevent regressions, open code the requirement to apply nvidia_bugs only on the root bus. Signed-off-by: Lukas Wunner <lukas@wunner.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/4d5477c1d76b2f0387a780f2142bbcdd9fee869b.1465690253.git.lukas@wunner.de Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-07-27perf/x86: Fix undefined shift on 32-bit kernelsAndrey Ryabinin1-1/+1
commit 6d6f2833bfbf296101f9f085e10488aef2601ba5 upstream. Jim reported: UBSAN: Undefined behaviour in arch/x86/events/intel/core.c:3708:12 shift exponent 35 is too large for 32-bit type 'long unsigned int' The use of 'unsigned long' type obviously is not correct here, make it 'unsigned long long' instead. Reported-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Imre Palik <imrep@amazon.de> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Fixes: 2c33645d366d ("perf/x86: Honor the architectural performance monitoring version") Link: http://lkml.kernel.org/r/1462974711-10037-1-git-send-email-aryabinin@virtuozzo.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Kevin Christopher <kevinc@vmware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-07-27KVM: nVMX: VMX instructions: fix segment checks when L1 is in long mode.Quentin Casasnovas1-12/+11
commit ff30ef40deca4658e27b0c596e7baf39115e858f upstream. I couldn't get Xen to boot a L2 HVM when it was nested under KVM - it was getting a GP(0) on a rather unspecial vmread from Xen: (XEN) ----[ Xen-4.7.0-rc x86_64 debug=n Not tainted ]---- (XEN) CPU: 1 (XEN) RIP: e008:[<ffff82d0801e629e>] vmx_get_segment_register+0x14e/0x450 (XEN) RFLAGS: 0000000000010202 CONTEXT: hypervisor (d1v0) (XEN) rax: ffff82d0801e6288 rbx: ffff83003ffbfb7c rcx: fffffffffffab928 (XEN) rdx: 0000000000000000 rsi: 0000000000000000 rdi: ffff83000bdd0000 (XEN) rbp: ffff83000bdd0000 rsp: ffff83003ffbfab0 r8: ffff830038813910 (XEN) r9: ffff83003faf3958 r10: 0000000a3b9f7640 r11: ffff83003f82d418 (XEN) r12: 0000000000000000 r13: ffff83003ffbffff r14: 0000000000004802 (XEN) r15: 0000000000000008 cr0: 0000000080050033 cr4: 00000000001526e0 (XEN) cr3: 000000003fc79000 cr2: 0000000000000000 (XEN) ds: 0000 es: 0000 fs: 0000 gs: 0000 ss: 0000 cs: e008 (XEN) Xen code around <ffff82d0801e629e> (vmx_get_segment_register+0x14e/0x450): (XEN) 00 00 41 be 02 48 00 00 <44> 0f 78 74 24 08 0f 86 38 56 00 00 b8 08 68 00 (XEN) Xen stack trace from rsp=ffff83003ffbfab0: ... (XEN) Xen call trace: (XEN) [<ffff82d0801e629e>] vmx_get_segment_register+0x14e/0x450 (XEN) [<ffff82d0801f3695>] get_page_from_gfn_p2m+0x165/0x300 (XEN) [<ffff82d0801bfe32>] hvmemul_get_seg_reg+0x52/0x60 (XEN) [<ffff82d0801bfe93>] hvm_emulate_prepare+0x53/0x70 (XEN) [<ffff82d0801ccacb>] handle_mmio+0x2b/0xd0 (XEN) [<ffff82d0801be591>] emulate.c#_hvm_emulate_one+0x111/0x2c0 (XEN) [<ffff82d0801cd6a4>] handle_hvm_io_completion+0x274/0x2a0 (XEN) [<ffff82d0801f334a>] __get_gfn_type_access+0xfa/0x270 (XEN) [<ffff82d08012f3bb>] timer.c#add_entry+0x4b/0xb0 (XEN) [<ffff82d08012f80c>] timer.c#remove_entry+0x7c/0x90 (XEN) [<ffff82d0801c8433>] hvm_do_resume+0x23/0x140 (XEN) [<ffff82d0801e4fe7>] vmx_do_resume+0xa7/0x140 (XEN) [<ffff82d080164aeb>] context_switch+0x13b/0xe40 (XEN) [<ffff82d080128e6e>] schedule.c#schedule+0x22e/0x570 (XEN) [<ffff82d08012c0cc>] softirq.c#__do_softirq+0x5c/0x90 (XEN) [<ffff82d0801602c5>] domain.c#idle_loop+0x25/0x50 (XEN) (XEN) (XEN) **************************************** (XEN) Panic on CPU 1: (XEN) GENERAL PROTECTION FAULT (XEN) [error_code=0000] (XEN) **************************************** Tracing my host KVM showed it was the one injecting the GP(0) when emulating the VMREAD and checking the destination segment permissions in get_vmx_mem_address(): 3) | vmx_handle_exit() { 3) | handle_vmread() { 3) | nested_vmx_check_permission() { 3) | vmx_get_segment() { 3) 0.074 us | vmx_read_guest_seg_base(); 3) 0.065 us | vmx_read_guest_seg_selector(); 3) 0.066 us | vmx_read_guest_seg_ar(); 3) 1.636 us | } 3) 0.058 us | vmx_get_rflags(); 3) 0.062 us | vmx_read_guest_seg_ar(); 3) 3.469 us | } 3) | vmx_get_cs_db_l_bits() { 3) 0.058 us | vmx_read_guest_seg_ar(); 3) 0.662 us | } 3) | get_vmx_mem_address() { 3) 0.068 us | vmx_cache_reg(); 3) | vmx_get_segment() { 3) 0.074 us | vmx_read_guest_seg_base(); 3) 0.068 us | vmx_read_guest_seg_selector(); 3) 0.071 us | vmx_read_guest_seg_ar(); 3) 1.756 us | } 3) | kvm_queue_exception_e() { 3) 0.066 us | kvm_multiple_exception(); 3) 0.684 us | } 3) 4.085 us | } 3) 9.833 us | } 3) + 10.366 us | } Cross-checking the KVM/VMX VMREAD emulation code with the Intel Software Developper Manual Volume 3C - "VMREAD - Read Field from Virtual-Machine Control Structure", I found that we're enforcing that the destination operand is NOT located in a read-only data segment or any code segment when the L1 is in long mode - BUT that check should only happen when it is in protected mode. Shuffling the code a bit to make our emulation follow the specification allows me to boot a Xen dom0 in a nested KVM and start HVM L2 guests without problems. Fixes: f9eb4af67c9d ("KVM: nVMX: VMX instructions: add checks for #GP/#SS exceptions") Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com> Cc: Eugene Korenevsky <ekorenevsky@gmail.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-07-27x86/amd_nb: Fix boot crash on non-AMD systemsBorislav Petkov1-2/+2
commit 1ead852dd88779eda12cb09cc894a03d9abfe1ec upstream. Fix boot crash that triggers if this driver is built into a kernel and run on non-AMD systems. AMD northbridges users call amd_cache_northbridges() and it returns a negative value to signal that we weren't able to cache/detect any northbridges on the system. At least, it should do so as all its callers expect it to do so. But it does return a negative value only when kmalloc() fails. Fix it to return -ENODEV if there are no NBs cached as otherwise, amd_nb users like amd64_edac, for example, which relies on it to know whether it should load or not, gets loaded on systems like Intel Xeons where it shouldn't. Reported-and-tested-by: Tony Battersby <tonyb@cybernetics.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1466097230-5333-2-git-send-email-bp@alien8.de Link: https://lkml.kernel.org/r/5761BEB0.9000807@cybernetics.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-07-27kprobes/x86: Clear TF bit in fault on single-steppingMasami Hiramatsu1-0/+12
commit dcfc47248d3f7d28df6f531e6426b933de94370d upstream. Fix kprobe_fault_handler() to clear the TF (trap flag) bit of the flags register in the case of a fault fixup on single-stepping. If we put a kprobe on the instruction which caused a page fault (e.g. actual mov instructions in copy_user_*), that fault happens on the single-stepping buffer. In this case, kprobes resets running instance so that the CPU can retry execution on the original ip address. However, current code forgets to reset the TF bit. Since this fault happens with TF bit set for enabling single-stepping, when it retries, it causes a debug exception and kprobes can not handle it because it already reset itself. On the most of x86-64 platform, it can be easily reproduced by using kprobe tracer. E.g. # cd /sys/kernel/debug/tracing # echo p copy_user_enhanced_fast_string+5 > kprobe_events # echo 1 > events/kprobes/enable And you'll see a kernel panic on do_debug(), since the debug trap is not handled by kprobes. To fix this problem, we just need to clear the TF bit when resetting running kprobe. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: systemtap@sourceware.org Link: http://lkml.kernel.org/r/20160611140648.25885.37482.stgit@devbox [ Updated the comments. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-07-27x86, build: copy ldlinux.c32 to image.isoH. Peter Anvin1-0/+3
commit 9c77679cadb118c0aa99e6f88533d91765a131ba upstream. For newer versions of Syslinux, we need ldlinux.c32 in addition to isolinux.bin to reside on the boot disk, so if the latter is found, copy it, too, to the isoimage tree. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-24x86/entry/traps: Don't force in_interrupt() to return true in IST handlersAndy Lutomirski1-10/+10
commit aaee8c3c5cce2d9107310dd9f3026b4f901d441c upstream. Forcing in_interrupt() to return true if we're not in a bona fide interrupt confuses the softirq code. This fixes warnings like: NOHZ: local_softirq_pending 282 ... which can happen when running things like selftests/x86. This will change perf's static percpu buffer usage in IST context. I think this is okay, and it's changing the behavior to match historical (pre-4.0) behavior. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 959274753857 ("x86, traps: Track entry into and exit from IST context") Link: http://lkml.kernel.org/r/cdc215f94d118d691d73df35275022331156fb45.1464130360.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-24KVM: x86: fix OOPS after invalid KVM_SET_DEBUGREGSPaolo Bonzini1-0/+5
commit d14bdb553f9196169f003058ae1cdabe514470e6 upstream. MOV to DR6 or DR7 causes a #GP if an attempt is made to write a 1 to any of bits 63:32. However, this is not detected at KVM_SET_DEBUGREGS time, and the next KVM_RUN oopses: general protection fault: 0000 [#1] SMP CPU: 2 PID: 14987 Comm: a.out Not tainted 4.4.9-300.fc23.x86_64 #1 Hardware name: LENOVO 2325F51/2325F51, BIOS G2ET32WW (1.12 ) 05/30/2012 [...] Call Trace: [<ffffffffa072c93d>] kvm_arch_vcpu_ioctl_run+0x141d/0x14e0 [kvm] [<ffffffffa071405d>] kvm_vcpu_ioctl+0x33d/0x620 [kvm] [<ffffffff81241648>] do_vfs_ioctl+0x298/0x480 [<ffffffff812418a9>] SyS_ioctl+0x79/0x90 [<ffffffff817a0f2e>] entry_SYSCALL_64_fastpath+0x12/0x71 Code: 55 83 ff 07 48 89 e5 77 27 89 ff ff 24 fd 90 87 80 81 0f 23 fe 5d c3 0f 23 c6 5d c3 0f 23 ce 5d c3 0f 23 d6 5d c3 0f 23 de 5d c3 <0f> 23 f6 5d c3 0f 0b 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 RIP [<ffffffff810639eb>] native_set_debugreg+0x2b/0x40 RSP <ffff88005836bd50> Testcase (beautified/reduced from syzkaller output): #include <unistd.h> #include <sys/syscall.h> #include <string.h> #include <stdint.h> #include <linux/kvm.h> #include <fcntl.h> #include <sys/ioctl.h> long r[8]; int main() { struct kvm_debugregs dr = { 0 }; r[2] = open("/dev/kvm", O_RDONLY); r[3] = ioctl(r[2], KVM_CREATE_VM, 0); r[4] = ioctl(r[3], KVM_CREATE_VCPU, 7); memcpy(&dr, "\x5d\x6a\x6b\xe8\x57\x3b\x4b\x7e\xcf\x0d\xa1\x72" "\xa3\x4a\x29\x0c\xfc\x6d\x44\x00\xa7\x52\xc7\xd8" "\x00\xdb\x89\x9d\x78\xb5\x54\x6b\x6b\x13\x1c\xe9" "\x5e\xd3\x0e\x40\x6f\xb4\x66\xf7\x5b\xe3\x36\xcb", 48); r[7] = ioctl(r[4], KVM_SET_DEBUGREGS, &dr); r[6] = ioctl(r[4], KVM_RUN, 0); } Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-08xen: use same main loop for counting and remapping pagesJuergen Gross1-39/+26
commit dd14be92fbf5bc1ef7343f34968440e44e21b46a upstream. Instead of having two functions for cycling through the E820 map in order to count to be remapped pages and remap them later, just use one function with a caller supplied sub-function called for each region to be processed. This eliminates the possibility of a mismatch between both loops which showed up in certain configurations. Suggested-by: Ed Swierk <eswierk@skyportsystems.com> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-01xen/x86: actually allocate legacy interrupts on PV guestsStefano Stabellini1-2/+5
commit 702f926067d2a4b28c10a3c41a1172dd62d9e735 upstream. b4ff8389ed14 is incomplete: relies on nr_legacy_irqs() to get the number of legacy interrupts when actually nr_legacy_irqs() returns 0 after probe_8259A(). Use NR_IRQS_LEGACY instead. Signed-off-by: Stefano Stabellini <sstabellini@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-01KVM: x86: mask CPUID(0xD,0x1).EAX against host valuePaolo Bonzini1-0/+1
commit 316314cae15fb0e3869b76b468f59a0c83ac3d4e upstream. This ensures that the guest doesn't see XSAVE extensions (e.g. xgetbv1 or xsavec) that the host lacks. Cc: stable@vger.kernel.org Reviewed-by: Radim Krčmář <rkrcmar@redhat.com> [4.5 does have CPUID_D_1_EAX, but earlier kernels don't, so use the numeric value. This is consistent with other occurrences of cpuid_mask in arch/x86/kvm/cpuid.c - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-01KVM: x86: fix ordering of cr0 initialization code in vmx_cpu_resetBruce Rogers1-1/+1
commit f24632475d4ffed5626abbfab7ef30a128dd1474 upstream. Commit d28bc9dd25ce reversed the order of two lines which initialize cr0, allowing the current (old) cr0 value to mess up vcpu initialization. This was observed in the checks for cr0 X86_CR0_WP bit in the context of kvm_mmu_reset_context(). Besides, setting vcpu->arch.cr0 after vmx_set_cr0() is completely redundant. Change the order back to ensure proper vcpu initialization. The combination of booting with ovmf firmware when guest vcpus > 1 and kvm's ept=N option being set results in a VM-entry failure. This patch fixes that. Fixes: d28bc9dd25ce ("KVM: x86: INIT and reset sequences are different") Signed-off-by: Bruce Rogers <brogers@suse.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-01KVM: MTRR: remove MSR 0x2f8Andy Honig1-2/+0
commit 9842df62004f366b9fed2423e24df10542ee0dc5 upstream. MSR 0x2f8 accessed the 124th Variable Range MTRR ever since MTRR support was introduced by 9ba075a664df ("KVM: MTRR support"). 0x2f8 became harmful when 910a6aae4e2e ("KVM: MTRR: exactly define the size of variable MTRRs") shrinked the array of VR MTRRs from 256 to 8, which made access to index 124 out of bounds. The surrounding code only WARNs in this situation, thus the guest gained a limited read/write access to struct kvm_arch_vcpu. 0x2f8 is not a valid VR MTRR MSR, because KVM has/advertises only 16 VR MTRR MSRs, 0x200-0x20f. Every VR MTRR is set up using two MSRs, 0x2f8 was treated as a PHYSBASE and 0x2f9 would be its PHYSMASK, but 0x2f9 was not implemented in KVM, therefore 0x2f8 could never do anything useful and getting rid of it is safe. This fixes CVE-2016-3713. Fixes: 910a6aae4e2e ("KVM: MTRR: exactly define the size of variable MTRRs") Reported-by: David Matlack <dmatlack@google.com> Signed-off-by: Andy Honig <ahonig@google.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-01perf/x86/intel/pt: Generate PMI in the STOP region as wellAlexander Shishkin1-0/+2
commit ab92b232ae05c382c3df0e3d6a5c6d16b639ac8c upstream. Currently, the PT driver always sets the PMI bit one region (page) before the STOP region so that we can wake up the consumer before we run out of room in the buffer and have to disable the event. However, we also need an interrupt in the last output region, so that we actually get to disable the event (if no more room from new data is available at that point), otherwise hardware just quietly refuses to start, but the event is scheduled in and we end up losing trace data till the event gets removed. For a cpu-wide event it is even worse since there may not be any re-scheduling at all and no chance for the ring buffer code to notice that its buffer is filled up and the event needs to be disabled (so that the consumer can re-enable it when it finishes reading the data out). In other words, all the trace data will be lost after the buffer gets filled up. This patch makes PT also generate a PMI when the last output region is full. Reported-by: Markus Metzger <markus.t.metzger@intel.com> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: vince@deater.net Link: http://lkml.kernel.org/r/1462886313-13660-2-git-send-email-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-11ACPI / processor: Request native thermal interrupt handling via _OSCSrinivas Pandruvada1-0/+3
commit a21211672c9a1d730a39aa65d4a5b3414700adfb upstream. There are several reports of freeze on enabling HWP (Hardware PStates) feature on Skylake-based systems by the Intel P-states driver. The root cause is identified as the HWP interrupts causing BIOS code to freeze. HWP interrupts use the thermal LVT which can be handled by Linux natively, but on the affected Skylake-based systems SMM will respond to it by default. This is a problem for several reasons: - On the affected systems the SMM thermal LVT handler is broken (it will crash when invoked) and a BIOS update is necessary to fix it. - With thermal interrupt handled in SMM we lose all of the reporting features of the arch/x86/kernel/cpu/mcheck/therm_throt driver. - Some thermal drivers like x86-package-temp depend on the thermal threshold interrupts signaled via the thermal LVT. - The HWP interrupts are useful for debugging and tuning performance (if the kernel can handle them). The native handling of thermal interrupts needs to be enabled because of that. This requires some way to tell SMM that the OS can handle thermal interrupts. That can be done by using _OSC/_PDC in processor scope very early during ACPI initialization. The meaning of _OSC/_PDC bit 12 in processor scope is whether or not the OS supports native handling of interrupts for Collaborative Processor Performance Control (CPPC) notifications. Since on HWP-capable systems CPPC is a firmware interface to HWP, setting this bit effectively tells the firmware that the OS will handle thermal interrupts natively going forward. For details on _OSC/_PDC refer to: http://www.intel.com/content/www/us/en/standards/processor-vendor-specific-acpi-specification.html To implement the _OSC/_PDC handshake as described, introduce a new function, acpi_early_processor_osc(), that walks the ACPI namespace looking for ACPI processor objects and invokes _OSC for them with bit 12 in the capabilities buffer set and terminates the namespace walk on the first success. Also modify intel_thermal_interrupt() to clear HWP status bits in the HWP_STATUS MSR to acknowledge HWP interrupts (which prevents them from firing continuously). Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> [ rjw: Subject & changelog, function rename ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-11x86/sysfb_efi: Fix valid BAR address range checkWang YanQing1-2/+12
commit c10fcb14c7afd6688c7b197a814358fecf244222 upstream. The code for checking whether a BAR address range is valid will break out of the loop when a start address of 0x0 is encountered. This behaviour is wrong since by breaking out of the loop we may miss the BAR that describes the EFI frame buffer in a later iteration. Because of this bug I can't use video=efifb: boot parameter to get efifb on my new ThinkPad E550 for my old linux system hard disk with 3.10 kernel. In 3.10, efifb is the only choice due to DRM/I915 not supporting the GPU. This patch also add a trivial optimization to break out after we find the frame buffer address range without testing later BARs. Signed-off-by: Wang YanQing <udknight@gmail.com> [ Rewrote changelog. ] Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Reviewed-by: Peter Jones <pjones@redhat.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: David Herrmann <dh.herrmann@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1462454061-21561-2-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-11x86/tsc: Read all ratio bits from MSR_PLATFORM_INFOChen Yu1-1/+1
commit 886123fb3a8656699dff40afa0573df359abeb18 upstream. Currently we read the tsc radio: ratio = (MSR_PLATFORM_INFO >> 8) & 0x1f; Thus we get bit 8-12 of MSR_PLATFORM_INFO, however according to the SDM (35.5), the ratio bits are bit 8-15. Ignoring the upper bits can result in an incorrect tsc ratio, which causes the TSC calibration and the Local APIC timer frequency to be incorrect. Fix this problem by masking 0xff instead. [ tglx: Massaged changelog ] Fixes: 7da7c1561366 "x86, tsc: Add static (MSR) TSC calibration on Intel Atom SoCs" Signed-off-by: Chen Yu <yu.c.chen@intel.com> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Bin Gao <bin.gao@intel.com> Cc: Len Brown <lenb@kernel.org> Link: http://lkml.kernel.org/r/1462505619-5516-1-git-send-email-yu.c.chen@intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-05x86/mm/kmmio: Fix mmiotrace for hugepagesKarol Herbst1-29/+59
commit cfa52c0cfa4d727aa3e457bf29aeff296c528a08 upstream. Because Linux might use bigger pages than the 4K pages to handle those mmio ioremaps, the kmmio code shouldn't rely on the pade id as it currently does. Using the memory address instead of the page id lets us look up how big the page is and what its base address is, so that we won't get a page fault within the same page twice anymore. Tested-by: Pierre Moreau <pierre.morrow@free.fr> Signed-off-by: Karol Herbst <nouveau@karolherbst.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: linux-mm@kvack.org Cc: linux-x86_64@vger.kernel.org Cc: nouveau@lists.freedesktop.org Cc: pq@iki.fi Cc: rostedt@goodmis.org Link: http://lkml.kernel.org/r/1456966991-6861-1-git-send-email-nouveau@karolherbst.de Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-05x86/apic: Handle zero vector gracefully in clear_vector_irq()Keith Busch1-1/+2
commit 1bdb8970392a68489b469c3a330a1adb5ef61beb upstream. If x86_vector_alloc_irq() fails x86_vector_free_irqs() is invoked to cleanup the already allocated vectors. This subsequently calls clear_vector_irq(). The failed irq has no vector assigned, which triggers the BUG_ON(!vector) in clear_vector_irq(). We cannot suppress the call to x86_vector_free_irqs() for the failed interrupt, because the other data related to this irq must be cleaned up as well. So calling clear_vector_irq() with vector == 0 is legitimate. Remove the BUG_ON and return if vector is zero, [ tglx: Massaged changelog ] Fixes: b5dc8e6c21e7 "x86/irq: Use hierarchical irqdomain to manage CPU interrupt vectors" Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-05crypto: sha1-mb - use corrcet pointer while completing jobsXiaodong Liu1-2/+2
commit 0851561d9c965df086ef8a53f981f5f95a57c2c8 upstream. In sha_complete_job, incorrect mcryptd_hash_request_ctx pointer is used when check and complete other jobs. If the memory of first completed req is freed, while still completing other jobs in the func, kernel will crash since NULL pointer is assigned to RIP. Signed-off-by: Xiaodong Liu <xiaodong.liu@intel.com> Acked-by: Tim Chen <tim.c.chen@linux.intel.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-05x86/mm/xen: Suppress hugetlbfs in PV guestsJan Beulich1-0/+1
commit 103f6112f253017d7062cd74d17f4a514ed4485c upstream. Huge pages are not normally available to PV guests. Not suppressing hugetlbfs use results in an endless loop of page faults when user mode code tries to access a hugetlbfs mapped area (since the hypervisor denies such PTEs to be created, but error indications can't be propagated out of xen_set_pte_at(), just like for various of its siblings), and - once killed in an oops like this: kernel BUG at .../fs/hugetlbfs/inode.c:428! invalid opcode: 0000 [#1] SMP ... RIP: e030:[<ffffffff811c333b>] [<ffffffff811c333b>] remove_inode_hugepages+0x25b/0x320 ... Call Trace: [<ffffffff811c3415>] hugetlbfs_evict_inode+0x15/0x40 [<ffffffff81167b3d>] evict+0xbd/0x1b0 [<ffffffff8116514a>] __dentry_kill+0x19a/0x1f0 [<ffffffff81165b0e>] dput+0x1fe/0x220 [<ffffffff81150535>] __fput+0x155/0x200 [<ffffffff81079fc0>] task_work_run+0x60/0xa0 [<ffffffff81063510>] do_exit+0x160/0x400 [<ffffffff810637eb>] do_group_exit+0x3b/0xa0 [<ffffffff8106e8bd>] get_signal+0x1ed/0x470 [<ffffffff8100f854>] do_signal+0x14/0x110 [<ffffffff810030e9>] prepare_exit_to_usermode+0xe9/0xf0 [<ffffffff814178a5>] retint_user+0x8/0x13 This is CVE-2016-3961 / XSA-174. Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Juergen Gross <JGross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: xen-devel <xen-devel@lists.xenproject.org> Link: http://lkml.kernel.org/r/57188ED802000078000E431C@prv-mh.provo.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-05kvm: x86: do not leak guest xcr0 into host interrupt handlersDavid Matlack1-6/+4
commit fc5b7f3bf1e1414bd4e91db6918c85ace0c873a5 upstream. An interrupt handler that uses the fpu can kill a KVM VM, if it runs under the following conditions: - the guest's xcr0 register is loaded on the cpu - the guest's fpu context is not loaded - the host is using eagerfpu Note that the guest's xcr0 register and fpu context are not loaded as part of the atomic world switch into "guest mode". They are loaded by KVM while the cpu is still in "host mode". Usage of the fpu in interrupt context is gated by irq_fpu_usable(). The interrupt handler will look something like this: if (irq_fpu_usable()) { kernel_fpu_begin(); [... code that uses the fpu ...] kernel_fpu_end(); } As long as the guest's fpu is not loaded and the host is using eager fpu, irq_fpu_usable() returns true (interrupted_kernel_fpu_idle() returns true). The interrupt handler proceeds to use the fpu with the guest's xcr0 live. kernel_fpu_begin() saves the current fpu context. If this uses XSAVE[OPT], it may leave the xsave area in an undesirable state. According to the SDM, during XSAVE bit i of XSTATE_BV is not modified if bit i is 0 in xcr0. So it's possible that XSTATE_BV[i] == 1 and xcr0[i] == 0 following an XSAVE. kernel_fpu_end() restores the fpu context. Now if any bit i in XSTATE_BV == 1 while xcr0[i] == 0, XRSTOR generates a #GP. The fault is trapped and SIGSEGV is delivered to the current process. Only pre-4.2 kernels appear to be vulnerable to this sequence of events. Commit 653f52c ("kvm,x86: load guest FPU context more eagerly") from 4.2 forces the guest's fpu to always be loaded on eagerfpu hosts. This patch fixes the bug by keeping the host's xcr0 loaded outside of the interrupts-disabled region where KVM switches into guest mode. Suggested-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: David Matlack <dmatlack@google.com> [Move load after goto cancel_injection. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-05x86/mce: Avoid using object after free in genpoolTony Luck1-2/+2
commit a3125494cff084b098c80bb36fbe2061ffed9d52 upstream. When we loop over all queued machine check error records to pass them to the registered notifiers we use llist_for_each_entry(). But the loop calls gen_pool_free() for the entry in the body of the loop - and then the iterator looks at node->next after the free. Use llist_for_each_entry_safe() instead. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Gong Chen <gong.chen@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-edac <linux-edac@vger.kernel.org> Link: http://lkml.kernel.org/r/0205920@agluck-desk.sc.intel.com Link: http://lkml.kernel.org/r/1459929916-12852-4-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-20Revert "PCI, x86: Implement pcibios_alloc_irq() and pcibios_free_irq()"Bjorn Helgaas4-15/+29
commit 6c777e8799a93e3bdb67bec622429e1b48dc90fb upstream. 991de2e59090 ("PCI, x86: Implement pcibios_alloc_irq() and pcibios_free_irq()") appeared in v4.3 and helps support IOAPIC hotplug. Олег reported that the Elcus-1553 TA1-PCI driver worked in v4.2 but not v4.3 and bisected it to 991de2e59090. Sunjin reported that the RocketRAID 272x driver worked in v4.2 but not v4.3. In both cases booting with "pci=routirq" is a workaround. I think the problem is that after 991de2e59090, we no longer call pcibios_enable_irq() for upstream bridges. Prior to 991de2e59090, when a driver called pci_enable_device(), we recursively called pcibios_enable_irq() for upstream bridges via pci_enable_bridge(). After 991de2e59090, we call pcibios_enable_irq() from pci_device_probe() instead of the pci_enable_device() path, which does *not* call pcibios_enable_irq() for upstream bridges. Revert 991de2e59090 to fix these driver regressions. Link: https://bugzilla.kernel.org/show_bug.cgi?id=111211 Fixes: 991de2e59090 ("PCI, x86: Implement pcibios_alloc_irq() and pcibios_free_irq()") Reported-and-tested-by: Олег Мороз <oleg.moroz@mcc.vniiem.ru> Reported-by: Sunjin Yang <fan4326@gmail.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Rafael J. Wysocki <rafael@kernel.org> CC: Jiang Liu <jiang.liu@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-20Revert "PCI: Add helpers to manage pci_dev->irq and pci_dev->irq_managed"Bjorn Helgaas2-6/+8
commit 67b4eab91caf2ad574cab1b17ae09180ea2e116e upstream. Revert 811a4e6fce09 ("PCI: Add helpers to manage pci_dev->irq and pci_dev->irq_managed"). This is part of reverting 991de2e59090 ("PCI, x86: Implement pcibios_alloc_irq() and pcibios_free_irq()") to fix regressions it introduced. Link: https://bugzilla.kernel.org/show_bug.cgi?id=111211 Fixes: 991de2e59090 ("PCI, x86: Implement pcibios_alloc_irq() and pcibios_free_irq()") Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Rafael J. Wysocki <rafael@kernel.org> CC: Jiang Liu <jiang.liu@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-20Revert "x86/PCI: Don't alloc pcibios-irq when MSI is enabled"Bjorn Helgaas1-8/+0
commit fe25d078874f2c29c38f4160467d74f5756537c9 upstream. Revert 8affb487d4a4 ("x86/PCI: Don't alloc pcibios-irq when MSI is enabled"). This is part of reverting 991de2e59090 ("PCI, x86: Implement pcibios_alloc_irq() and pcibios_free_irq()") to fix regressions it introduced. Link: https://bugzilla.kernel.org/show_bug.cgi?id=111211 Fixes: 991de2e59090 ("PCI, x86: Implement pcibios_alloc_irq() and pcibios_free_irq()") Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Rafael J. Wysocki <rafael@kernel.org> CC: Jiang Liu <jiang.liu@linux.intel.com> CC: Joerg Roedel <jroedel@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-20KVM: x86: reduce default value of halt_poll_ns parameterPaolo Bonzini1-1/+1
commit 14ebda3394fd3e5388747e742e510b0802a65d24 upstream. Windows lets applications choose the frequency of the timer tick, and in Windows 10 the maximum rate was changed from 1024 Hz to 2048 Hz. Unfortunately, because of the way the Windows API works, most applications who need a higher rate than the default 64 Hz will just do timeGetDevCaps(&tc, sizeof(tc)); timeBeginPeriod(tc.wPeriodMin); and pick the maximum rate. This causes very high CPU usage when playing media or games on Windows 10, even if the guest does not actually use the CPU very much, because the frequent timer tick causes halt_poll_ns to kick in. There is no really good solution, especially because Microsoft could sooner or later bump the limit to 4096 Hz, but for now the best we can do is lower a bit the upper limit for halt_poll_ns. :-( Reported-by: Jon Panozzo <jonp@lime-technology.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-20KVM: x86: Inject pending interrupt even if pending nmi existYuki Shibuya1-10/+10
commit 321c5658c5e9192dea0d58ab67cf1791e45b2b26 upstream. Non maskable interrupts (NMI) are preferred to interrupts in current implementation. If a NMI is pending and NMI is blocked by the result of nmi_allowed(), pending interrupt is not injected and enable_irq_window() is not executed, even if interrupts injection is allowed. In old kernel (e.g. 2.6.32), schedule() is often called in NMI context. In this case, interrupts are needed to execute iret that intends end of NMI. The flag of blocking new NMI is not cleared until the guest execute the iret, and interrupts are blocked by pending NMI. Due to this, iret can't be invoked in the guest, and the guest is starved until block is cleared by some events (e.g. canceling injection). This patch injects pending interrupts, when it's allowed, even if NMI is blocked. And, If an interrupts is pending after executing inject_pending_event(), enable_irq_window() is executed regardless of NMI pending counter. Signed-off-by: Yuki Shibuya <shibuya.yk@ncos.nec.co.jp> Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12perf/x86/intel: Fix PEBS data source interpretation on Nehalem/WestmereAndi Kleen3-1/+14
commit e17dc65328057c00db7e1bfea249c8771a78b30b upstream. Jiri reported some time ago that some entries in the PEBS data source table in perf do not agree with the SDM. We investigated and the bits changed for Sandy Bridge, but the SDM was not updated. perf already implements the bits correctly for Sandy Bridge and later. This patch patches it up for Nehalem and Westmere. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: jolsa@kernel.org Link: http://lkml.kernel.org/r/1456871124-15985-1-git-send-email-andi@firstfloor.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12perf/x86/intel: Use PAGE_SIZE for PEBS buffer size on Core2Jiri Olsa2-2/+12
commit e72daf3f4d764c47fb71c9bdc7f9c54a503825b1 upstream. Using PAGE_SIZE buffers makes the WRMSR to PERF_GLOBAL_CTRL in intel_pmu_enable_all() mysteriously hang on Core2. As a workaround, we don't do this. The hard lockup is easily triggered by running 'perf test attr' repeatedly. Most of the time it gets stuck on sample session with small periods. # perf test attr -vv 14: struct perf_event_attr setup : --- start --- ... 'PERF_TEST_ATTR=/tmp/tmpuEKz3B /usr/bin/perf record -o /tmp/tmpuEKz3B/perf.data -c 123 kill >/dev/null 2>&1' ret 1 Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Andi Kleen <ak@linux.intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/r/20160301190352.GA8355@krava.redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12perf/x86/intel: Fix PEBS warning by only restoring active PMU in pmiKan Liang3-3/+29
commit c3d266c8a9838cc141b69548bc3b1b18808ae8c4 upstream. This patch tries to fix a PEBS warning found in my stress test. The following perf command can easily trigger the pebs warning or spurious NMI error on Skylake/Broadwell/Haswell platforms: sudo perf record -e 'cpu/umask=0x04,event=0xc4/pp,cycles,branches,ref-cycles,cache-misses,cache-references' --call-graph fp -b -c1000 -a Also the NMI watchdog must be enabled. For this case, the events number is larger than counter number. So perf has to do multiplexing. In perf_mux_hrtimer_handler, it does perf_pmu_disable(), schedule out old events, rotate_ctx, schedule in new events and finally perf_pmu_enable(). If the old events include precise event, the MSR_IA32_PEBS_ENABLE should be cleared when perf_pmu_disable(). The MSR_IA32_PEBS_ENABLE should keep 0 until the perf_pmu_enable() is called and the new event is precise event. However, there is a corner case which could restore PEBS_ENABLE to stale value during the above period. In perf_pmu_disable(), GLOBAL_CTRL will be set to 0 to stop overflow and followed PMI. But there may be pending PMI from an earlier overflow, which cannot be stopped. So even GLOBAL_CTRL is cleared, the kernel still be possible to get PMI. At the end of the PMI handler, __intel_pmu_enable_all() will be called, which will restore the stale values if old events haven't scheduled out. Once the stale pebs value is set, it's impossible to be corrected if the new events are non-precise. Because the pebs_enabled will be set to 0. x86_pmu.enable_all() will ignore the MSR_IA32_PEBS_ENABLE setting. As a result, the following NMI with stale PEBS_ENABLE trigger pebs warning. The pending PMI after enabled=0 will become harmless if the NMI handler does not change the state. This patch checks cpuc->enabled in pmi and only restore the state when PMU is active. Here is the dump: Call Trace: <NMI> [<ffffffff813c3a2e>] dump_stack+0x63/0x85 [<ffffffff810a46f2>] warn_slowpath_common+0x82/0xc0 [<ffffffff810a483a>] warn_slowpath_null+0x1a/0x20 [<ffffffff8100fe2e>] intel_pmu_drain_pebs_nhm+0x2be/0x320 [<ffffffff8100caa9>] intel_pmu_handle_irq+0x279/0x460 [<ffffffff810639b6>] ? native_write_msr_safe+0x6/0x40 [<ffffffff811f290d>] ? vunmap_page_range+0x20d/0x330 [<ffffffff811f2f11>] ? unmap_kernel_range_noflush+0x11/0x20 [<ffffffff8148379f>] ? ghes_copy_tofrom_phys+0x10f/0x2a0 [<ffffffff814839c8>] ? ghes_read_estatus+0x98/0x170 [<ffffffff81005a7d>] perf_event_nmi_handler+0x2d/0x50 [<ffffffff810310b9>] nmi_handle+0x69/0x120 [<ffffffff810316f6>] default_do_nmi+0xe6/0x100 [<ffffffff810317f2>] do_nmi+0xe2/0x130 [<ffffffff817aea71>] end_repeat_nmi+0x1a/0x1e [<ffffffff810639b6>] ? native_write_msr_safe+0x6/0x40 [<ffffffff810639b6>] ? native_write_msr_safe+0x6/0x40 [<ffffffff810639b6>] ? native_write_msr_safe+0x6/0x40 <<EOE>> <IRQ> [<ffffffff81006df8>] ? x86_perf_event_set_period+0xd8/0x180 [<ffffffff81006eec>] x86_pmu_start+0x4c/0x100 [<ffffffff8100722d>] x86_pmu_enable+0x28d/0x300 [<ffffffff811994d7>] perf_pmu_enable.part.81+0x7/0x10 [<ffffffff8119cb70>] perf_mux_hrtimer_handler+0x200/0x280 [<ffffffff8119c970>] ? __perf_install_in_context+0xc0/0xc0 [<ffffffff8110f92d>] __hrtimer_run_queues+0xfd/0x280 [<ffffffff811100d8>] hrtimer_interrupt+0xa8/0x190 [<ffffffff81199080>] ? __perf_read_group_add.part.61+0x1a0/0x1a0 [<ffffffff81051bd8>] local_apic_timer_interrupt+0x38/0x60 [<ffffffff817af01d>] smp_apic_timer_interrupt+0x3d/0x50 [<ffffffff817ad15c>] apic_timer_interrupt+0x8c/0xa0 <EOI> [<ffffffff81199080>] ? __perf_read_group_add.part.61+0x1a0/0x1a0 [<ffffffff81123de5>] ? smp_call_function_single+0xd5/0x130 [<ffffffff81123ddb>] ? smp_call_function_single+0xcb/0x130 [<ffffffff81199080>] ? __perf_read_group_add.part.61+0x1a0/0x1a0 [<ffffffff8119765a>] event_function_call+0x10a/0x120 [<ffffffff8119c660>] ? ctx_resched+0x90/0x90 [<ffffffff811971e0>] ? cpu_clock_event_read+0x30/0x30 [<ffffffff811976d0>] ? _perf_event_disable+0x60/0x60 [<ffffffff8119772b>] _perf_event_enable+0x5b/0x70 [<ffffffff81197388>] perf_event_for_each_child+0x38/0xa0 [<ffffffff811976d0>] ? _perf_event_disable+0x60/0x60 [<ffffffff811a0ffd>] perf_ioctl+0x12d/0x3c0 [<ffffffff8134d855>] ? selinux_file_ioctl+0x95/0x1e0 [<ffffffff8124a3a1>] do_vfs_ioctl+0xa1/0x5a0 [<ffffffff81036d29>] ? sched_clock+0x9/0x10 [<ffffffff8124a919>] SyS_ioctl+0x79/0x90 [<ffffffff817ac4b2>] entry_SYSCALL_64_fastpath+0x1a/0xa4 ---[ end trace aef202839fe9a71d ]--- Uhhuh. NMI received for unknown reason 2d on CPU 2. Do you have a strange power saving mode enabled? Signed-off-by: Kan Liang <kan.liang@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: http://lkml.kernel.org/r/1457046448-6184-1-git-send-email-kan.liang@intel.com [ Fixed various typos and other small details. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12perf/x86/pebs: Add workaround for broken OVFL status on HSW+Stephane Eranian1-0/+10
commit 8077eca079a212f26419c57226f28696b7100683 upstream. This patch fixes an issue with the GLOBAL_OVERFLOW_STATUS bits on Haswell, Broadwell and Skylake processors when using PEBS. The SDM stipulates that when the PEBS iterrupt threshold is crossed, an interrupt is posted and the kernel is interrupted. The kernel will find GLOBAL_OVF_SATUS bit 62 set indicating there are PEBS records to drain. But the bits corresponding to the actual counters should NOT be set. The kernel follows the SDM and assumes that all PEBS events are processed in the drain_pebs() callback. The kernel then checks for remaining overflows on any other (non-PEBS) events and processes these in the for_each_bit_set(&status) loop. As it turns out, under certain conditions on HSW and later processors, on PEBS buffer interrupt, bit 62 is set but the counter bits may be set as well. In that case, the kernel drains PEBS and generates SAMPLES with the EXACT tag, then it processes the counter bits, and generates normal (non-EXACT) SAMPLES. I ran into this problem by trying to understand why on HSW sampling on a PEBS event was sometimes returning SAMPLES without the EXACT tag. This should not happen on user level code because HSW has the eventing_ip which always point to the instruction that caused the event. The workaround in this patch simply ensures that the bits for the counters used for PEBS events are cleared after the PEBS buffer has been drained. With this fix 100% of the PEBS samples on my user code report the EXACT tag. Before: $ perf record -e cpu/event=0xd0,umask=0x81/upp ./multichase $ perf report -D | fgrep SAMPLES PERF_RECORD_SAMPLE(IP, 0x2): 11775/11775: 0x406de5 period: 73469 addr: 0 exact=Y \--- EXACT tag is missing After: $ perf record -e cpu/event=0xd0,umask=0x81/upp ./multichase $ perf report -D | fgrep SAMPLES PERF_RECORD_SAMPLE(IP, 0x4002): 11775/11775: 0x406de5 period: 73469 addr: 0 exact=Y \--- EXACT tag is set The problem tends to appear more often when multiple PEBS events are used. Signed-off-by: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: adrian.hunter@intel.com Cc: kan.liang@intel.com Cc: namhyung@kernel.org Link: http://lkml.kernel.org/r/1457034642-21837-3-git-send-email-eranian@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12x86/mm: TLB_REMOTE_SEND_IPI should count pagesNadav Amit1-3/+9
commit 18c98243ddf05a1827ad2c359c5ac051101e7ff7 upstream. TLB_REMOTE_SEND_IPI was recently introduced, but it counts bytes instead of pages. In addition, it does not report correctly the case in which flush_tlb_page flushes a page. Fix it to be consistent with other TLB counters. Fixes: 5b74283ab251b9d ("x86, mm: trace when an IPI is about to be sent") Signed-off-by: Nadav Amit <namit@vmware.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Rik van Riel <riel@redhat.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12x86/iopl: Fix iopl capability check on Xen PVAndy Lutomirski1-3/+9
commit c29016cf41fe9fa994a5ecca607cf5f1cd98801e upstream. iopl(3) is supposed to work if iopl is already 3, even if unprivileged. This didn't work right on Xen PV. Fix it. Reviewewd-by: Jan Beulich <JBeulich@suse.com> Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andrew Cooper <andrew.cooper3@citrix.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jan Beulich <JBeulich@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/8ce12013e6e4c0a44a97e316be4a6faff31bd5ea.1458162709.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12x86/iopl/64: Properly context-switch IOPL on Xen PVAndy Lutomirski3-1/+15
commit b7a584598aea7ca73140cb87b40319944dd3393f upstream. On Xen PV, regs->flags doesn't reliably reflect IOPL and the exit-to-userspace code doesn't change IOPL. We need to context switch it manually. I'm doing this without going through paravirt because this is specific to Xen PV. After the dust settles, we can merge this with the 32-bit code, tidy up the iopl syscall implementation, and remove the set_iopl pvop entirely. Fixes XSA-171. Reviewewd-by: Jan Beulich <JBeulich@suse.com> Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andrew Cooper <andrew.cooper3@citrix.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jan Beulich <JBeulich@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/693c3bd7aeb4d3c27c92c622b7d0f554a458173c.1458162709.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12x86/apic: Fix suspicious RCU usage in smp_trace_call_function_interrupt()Dave Jones1-1/+1
commit 7834c10313fb823e538f2772be78edcdeed2e6e3 upstream. Since 4.4, I've been able to trigger this occasionally: =============================== [ INFO: suspicious RCU usage. ] 4.5.0-rc7-think+ #3 Not tainted Cc: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/20160315012054.GA17765@codemonkey.org.uk Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> ------------------------------- ./arch/x86/include/asm/msr-trace.h:47 suspicious rcu_dereference_check() usage! other info that might help us debug this: RCU used illegally from idle CPU! rcu_scheduler_active = 1, debug_locks = 1 RCU used illegally from extended quiescent state! no locks held by swapper/3/0. stack backtrace: CPU: 3 PID: 0 Comm: swapper/3 Not tainted 4.5.0-rc7-think+ #3 ffffffff92f821e0 1f3e5c340597d7fc ffff880468e07f10 ffffffff92560c2a ffff880462145280 0000000000000001 ffff880468e07f40 ffffffff921376a6 ffffffff93665ea0 0000cc7c876d28da 0000000000000005 ffffffff9383dd60 Call Trace: <IRQ> [<ffffffff92560c2a>] dump_stack+0x67/0x9d [<ffffffff921376a6>] lockdep_rcu_suspicious+0xe6/0x100 [<ffffffff925ae7a7>] do_trace_write_msr+0x127/0x1a0 [<ffffffff92061c83>] native_apic_msr_eoi_write+0x23/0x30 [<ffffffff92054408>] smp_trace_call_function_interrupt+0x38/0x360 [<ffffffff92d1ca60>] trace_call_function_interrupt+0x90/0xa0 <EOI> [<ffffffff92ac5124>] ? cpuidle_enter_state+0x1b4/0x520 Move the entering_irq() call before ack_APIC_irq(), because entering_irq() tells the RCU susbstems to end the extended quiescent state, so that the following trace call in ack_APIC_irq() works correctly. Suggested-by: Andi Kleen <ak@linux.intel.com> Fixes: 4787c368a9bc "x86/tracing: Add irq_enter/exit() in smp_trace_reschedule_interrupt()" Signed-off-by: Dave Jones <davej@codemonkey.org.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-04-12x86/irq: Cure live lock in fixup_irqs()Thomas Gleixner2-18/+71
commit 551adc60573cb68e3d55cacca9ba1b7437313df7 upstream. Harry reported, that he's able to trigger a system freeze with cpu hot unplug. The freeze turned out to be a live lock caused by recent changes in irq_force_complete_move(). When fixup_irqs() and from there irq_force_complete_move() is called on the dying cpu, then all other cpus are in stop machine an wait for the dying cpu to complete the teardown. If there is a move of an interrupt pending then irq_force_complete_move() sends the cleanup IPI to the cpus in the old_domain mask and waits for them to clear the mask. That's obviously impossible as those cpus are firmly stuck in stop machine with interrupts disabled. I should have known that, but I completely overlooked it being concentrated on the locking issues around the vectors. And the existance of the call to __irq_complete_move() in the code, which actually sends the cleanup IPI made it reasonable to wait for that cleanup to complete. That call was bogus even before the recent changes as it was just a pointless distraction. We have to look at two cases: 1) The move_in_progress flag of the interrupt is set This means the ioapic has been updated with the new vector, but it has not fired yet. In theory there is a race: set_ioapic(new_vector) <-- Interrupt is raised before update is effective, i.e. it's raised on the old vector. So if the target cpu cannot handle that interrupt before the old vector is cleaned up, we get a spurious interrupt and in the worst case the ioapic irq line becomes stale, but my experiments so far have only resulted in spurious interrupts. But in case of cpu hotplug this should be a non issue because if the affinity update happens right before all cpus rendevouz in stop machine, there is no way that the interrupt can be blocked on the target cpu because all cpus loops first with interrupts enabled in stop machine, so the old vector is not yet cleaned up when the interrupt fires. So the only way to run into this issue is if the delivery of the interrupt on the apic/system bus would be delayed beyond the point where the target cpu disables interrupts in stop machine. I doubt that it can happen, but at least there is a theroretical chance. Virtualization might be able to expose this, but AFAICT the IOAPIC emulation is not as stupid as the real hardware. I've spent quite some time over the weekend to enforce that situation, though I was not able to trigger the delayed case. 2) The move_in_progress flag is not set and the old_domain cpu mask is not empty. That means, that an interrupt was delivered after the change and the cleanup IPI has been sent to the cpus in old_domain, but not all CPUs have responded to it yet. In both cases we can assume that the next interrupt will arrive on the new vector, so we can cleanup the old vectors on the cpus in the old_domain cpu mask. Fixes: 98229aa36caa "x86/irq: Plug vector cleanup race" Reported-by: Harry Junior <harryjr@outlook.fr> Tested-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Joe Lawrence <joe.lawrence@stratus.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Ben Hutchings <ben@decadent.org.uk> Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1603140931430.3657@nanos Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>