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2015-08-05Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-4/+4
Pull KVM fixes from Paolo Bonzini: "Just two very small & simple patches" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: MTRR: Use default type for non-MTRR-covered gfn before WARN_ON KVM: s390: Fix hang VCPU hang/loop regression
2015-08-05KVM: MTRR: Use default type for non-MTRR-covered gfn before WARN_ONAlex Williamson1-4/+4
The patch was munged on commit to re-order these tests resulting in excessive warnings when trying to do device assignment. Return to original ordering: https://lkml.org/lkml/2015/7/15/769 Fixes: 3e5d2fdceda1 ("KVM: MTRR: simplify kvm_mtrr_get_guest_memory_type") Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Reviewed-by: Xiao Guangrong <guangrong.xiao@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-08-01Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds13-154/+260
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "Fallout from the recent NMI fixes: make x86 LDT handling more robust. Also some EFI fixes" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/ldt: Make modify_ldt synchronous x86/xen: Probe target addresses in set_aliased_prot() before the hypercall x86/irq: Use the caller provided polarity setting in mp_check_pin_attr() efi: Check for NULL efi kernel parameters x86/efi: Use all 64 bit of efi_memmap in setup_e820()
2015-08-01Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds1-4/+4
Pull networking fixes from David Miller: 1) Must teardown SR-IOV before unregistering netdev in igb driver, from Alex Williamson. 2) Fix ipv6 route unreachable crash in IPVS, from Alex Gartrell. 3) Default route selection in ipv4 should take the prefix length, table ID, and TOS into account, from Julian Anastasov. 4) sch_plug must have a reset method in order to purge all buffered packets when the qdisc is reset, likewise for sch_choke, from WANG Cong. 5) Fix deadlock and races in slave_changelink/br_setport in bridging. From Nikolay Aleksandrov. 6) mlx4 bug fixes (wrong index in port even propagation to VFs, overzealous BUG_ON assertion, etc.) from Ido Shamay, Jack Morgenstein, and Or Gerlitz. 7) Turn off klog message about SCTP userspace interface compat that makes no sense at all, from Daniel Borkmann. 8) Fix unbounded restarts of inet frag eviction process, causing NMI watchdog soft lockup messages, from Florian Westphal. 9) Suspend/resume fixes for r8152 from Hayes Wang. 10) Fix busy loop when MSG_WAITALL|MSG_PEEK is used in TCP recv, from Sabrina Dubroca. 11) Fix performance regression when removing a lot of routes from the ipv4 routing tables, from Alexander Duyck. 12) Fix device leak in AF_PACKET, from Lars Westerhoff. 13) AF_PACKET also has a header length comparison bug due to signedness, from Alexander Drozdov. 14) Fix bug in EBPF tail call generation on x86, from Daniel Borkmann. 15) Memory leaks, TSO stats, watchdog timeout and other fixes to thunderx driver from Sunil Goutham and Thanneeru Srinivasulu. 16) act_bpf can leak memory when replacing programs, from Daniel Borkmann. 17) WOL packet fixes in gianfar driver, from Claudiu Manoil. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (79 commits) stmmac: fix missing MODULE_LICENSE in stmmac_platform gianfar: Enable device wakeup when appropriate gianfar: Fix suspend/resume for wol magic packet gianfar: Fix warning when CONFIG_PM off act_pedit: check binding before calling tcf_hash_release() net: sk_clone_lock() should only do get_net() if the parent is not a kernel socket net: sched: fix refcount imbalance in actions r8152: reset device when tx timeout r8152: add pre_reset and post_reset qlcnic: Fix corruption while copying act_bpf: fix memory leaks when replacing bpf programs net: thunderx: Fix for crash while BGX teardown net: thunderx: Add PCI driver shutdown routine net: thunderx: Fix crash when changing rss with mutliple traffic flows net: thunderx: Set watchdog timeout value net: thunderx: Wakeup TXQ only if CQE_TX are processed net: thunderx: Suppress alloc_pages() failure warnings net: thunderx: Fix TSO packet statistic net: thunderx: Fix memory leak when changing queue count net: thunderx: Fix RQ_DROP miscalculation ...
2015-07-31x86/ldt: Make modify_ldt synchronousAndy Lutomirski9-153/+210
modify_ldt() has questionable locking and does not synchronize threads. Improve it: redesign the locking and synchronize all threads' LDTs using an IPI on all modifications. This will dramatically slow down modify_ldt in multithreaded programs, but there shouldn't be any multithreaded programs that care about modify_ldt's performance in the first place. This fixes some fallout from the CVE-2015-5157 fixes. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Borislav Petkov <bp@suse.de> 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: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jan Beulich <jbeulich@suse.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: security@kernel.org <security@kernel.org> Cc: <stable@vger.kernel.org> Cc: xen-devel <xen-devel@lists.xen.org> Link: http://lkml.kernel.org/r/4c6978476782160600471bd865b318db34c7b628.1438291540.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-31x86/xen: Probe target addresses in set_aliased_prot() before the hypercallAndy Lutomirski1-0/+40
The update_va_mapping hypercall can fail if the VA isn't present in the guest's page tables. Under certain loads, this can result in an OOPS when the target address is in unpopulated vmap space. While we're at it, add comments to help explain what's going on. This isn't a great long-term fix. This code should probably be changed to use something like set_memory_ro. 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 <dvrabel@cantab.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jan Beulich <jbeulich@suse.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: security@kernel.org <security@kernel.org> Cc: <stable@vger.kernel.org> Cc: xen-devel <xen-devel@lists.xen.org> Link: http://lkml.kernel.org/r/0b0e55b995cda11e7829f140b833ef932fcabe3a.1438291540.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-31Merge tag 'efi-urgent' of ↵Ingo Molnar2-0/+9
git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into x86/urgent Pull EFI fixes from Matt Fleming: * Fix an EFI boot issue preventing a Parallels virtual machine from booting because the upper 32-bits of the EFI memmap pointer were being discarded in setup_e820(). (Dmitry Skorodumov) * Validate that the "efi" kernel parameter gets used with an argument, otherwise we will oops. (Ricardo Neri) Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-30x86/irq: Use the caller provided polarity setting in mp_check_pin_attr()Jiang Liu1-1/+1
Commit d32932d02e18 ("x86/irq: Convert IOAPIC to use hierarchical irqdomain interfaces") introduced a regression which causes malfunction of interrupt lines. The reason is that the conversion of mp_check_pin_attr() missed to update the polarity selection of the interrupt pin with the caller provided setting and instead uses a stale attribute value. That in turn results in chosing the wrong interrupt flow handler. Use the caller supplied setting to configure the pin correctly which also choses the correct interrupt flow handler. This restores the original behaviour and on the affected machine/driver (Surface Pro 3, i2c controller) all IOAPIC IRQ configuration are identical to v4.1. Fixes: d32932d02e18 ("x86/irq: Convert IOAPIC to use hierarchical irqdomain interfaces") Reported-and-tested-by: Matt Fleming <matt@codeblueprint.co.uk> Reported-and-tested-by: Chen Yu <yu.c.chen@intel.com> Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Chen Yu <yu.c.chen@intel.com> Cc: Yinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/1438242695-23531-1-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-30efi: Check for NULL efi kernel parametersRicardo Neri1-0/+5
Even though it is documented how to specifiy efi parameters, it is possible to cause a kernel panic due to a dereference of a NULL pointer when parsing such parameters if "efi" alone is given: PANIC: early exception 0e rip 10:ffffffff812fb361 error 0 cr2 0 [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.2.0-rc1+ #450 [ 0.000000] ffffffff81fe20a9 ffffffff81e03d50 ffffffff8184bb0f 00000000000003f8 [ 0.000000] 0000000000000000 ffffffff81e03e08 ffffffff81f371a1 64656c62616e6520 [ 0.000000] 0000000000000069 000000000000005f 0000000000000000 0000000000000000 [ 0.000000] Call Trace: [ 0.000000] [<ffffffff8184bb0f>] dump_stack+0x45/0x57 [ 0.000000] [<ffffffff81f371a1>] early_idt_handler_common+0x81/0xae [ 0.000000] [<ffffffff812fb361>] ? parse_option_str+0x11/0x90 [ 0.000000] [<ffffffff81f4dd69>] arch_parse_efi_cmdline+0x15/0x42 [ 0.000000] [<ffffffff81f376e1>] do_early_param+0x50/0x8a [ 0.000000] [<ffffffff8106b1b3>] parse_args+0x1e3/0x400 [ 0.000000] [<ffffffff81f37a43>] parse_early_options+0x24/0x28 [ 0.000000] [<ffffffff81f37691>] ? loglevel+0x31/0x31 [ 0.000000] [<ffffffff81f37a78>] parse_early_param+0x31/0x3d [ 0.000000] [<ffffffff81f3ae98>] setup_arch+0x2de/0xc08 [ 0.000000] [<ffffffff8109629a>] ? vprintk_default+0x1a/0x20 [ 0.000000] [<ffffffff81f37b20>] start_kernel+0x90/0x423 [ 0.000000] [<ffffffff81f37495>] x86_64_start_reservations+0x2a/0x2c [ 0.000000] [<ffffffff81f37582>] x86_64_start_kernel+0xeb/0xef [ 0.000000] RIP 0xffffffff81ba2efc This panic is not reproducible with "efi=" as this will result in a non-NULL zero-length string. Thus, verify that the pointer to the parameter string is not NULL. This is consistent with other parameter-parsing functions which check for NULL pointers. Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Dave Young <dyoung@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-07-30x86/efi: Use all 64 bit of efi_memmap in setup_e820()Dmitry Skorodumov1-0/+4
The efi_info structure stores low 32 bits of memory map in efi_memmap and high 32 bits in efi_memmap_hi. While constructing pointer in the setup_e820(), need to take into account all 64 bit of the pointer. It is because on 64bit machine the function efi_get_memory_map() may return full 64bit pointer and before the patch that pointer was truncated. The issue is triggered on Parallles virtual machine and fixed with this patch. Signed-off-by: Dmitry Skorodumov <sdmitry@parallels.com> Cc: Denis V. Lunev <den@openvz.org> Cc: <stable@vger.kernel.org> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-07-30ebpf, x86: fix general protection fault when tail call is invokedDaniel Borkmann1-4/+4
With eBPF JIT compiler enabled on x86_64, I was able to reliably trigger the following general protection fault out of an eBPF program with a simple tail call, f.e. tracex5 (or a stripped down version of it): [ 927.097918] general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC [...] [ 927.100870] task: ffff8801f228b780 ti: ffff880016a64000 task.ti: ffff880016a64000 [ 927.102096] RIP: 0010:[<ffffffffa002440d>] [<ffffffffa002440d>] 0xffffffffa002440d [ 927.103390] RSP: 0018:ffff880016a67a68 EFLAGS: 00010006 [ 927.104683] RAX: 5a5a5a5a5a5a5a5a RBX: 0000000000000000 RCX: 0000000000000001 [ 927.105921] RDX: 0000000000000000 RSI: ffff88014e438000 RDI: ffff880016a67e00 [ 927.107137] RBP: ffff880016a67c90 R08: 0000000000000000 R09: 0000000000000001 [ 927.108351] R10: 0000000000000000 R11: 0000000000000000 R12: ffff880016a67e00 [ 927.109567] R13: 0000000000000000 R14: ffff88026500e460 R15: ffff880220a81520 [ 927.110787] FS: 00007fe7d5c1f740(0000) GS:ffff880265000000(0000) knlGS:0000000000000000 [ 927.112021] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 927.113255] CR2: 0000003e7bbb91a0 CR3: 000000006e04b000 CR4: 00000000001407e0 [ 927.114500] Stack: [ 927.115737] ffffc90008cdb000 ffff880016a67e00 ffff88026500e460 ffff880220a81520 [ 927.117005] 0000000100000000 000000000000001b ffff880016a67aa8 ffffffff8106c548 [ 927.118276] 00007ffcdaf22e58 0000000000000000 0000000000000000 ffff880016a67ff0 [ 927.119543] Call Trace: [ 927.120797] [<ffffffff8106c548>] ? lookup_address+0x28/0x30 [ 927.122058] [<ffffffff8113d176>] ? __module_text_address+0x16/0x70 [ 927.123314] [<ffffffff8117bf0e>] ? is_ftrace_trampoline+0x3e/0x70 [ 927.124562] [<ffffffff810c1a0f>] ? __kernel_text_address+0x5f/0x80 [ 927.125806] [<ffffffff8102086f>] ? print_context_stack+0x7f/0xf0 [ 927.127033] [<ffffffff810f7852>] ? __lock_acquire+0x572/0x2050 [ 927.128254] [<ffffffff810f7852>] ? __lock_acquire+0x572/0x2050 [ 927.129461] [<ffffffff8119edfa>] ? trace_call_bpf+0x3a/0x140 [ 927.130654] [<ffffffff8119ee4a>] trace_call_bpf+0x8a/0x140 [ 927.131837] [<ffffffff8119edfa>] ? trace_call_bpf+0x3a/0x140 [ 927.133015] [<ffffffff8119f008>] kprobe_perf_func+0x28/0x220 [ 927.134195] [<ffffffff811a1668>] kprobe_dispatcher+0x38/0x60 [ 927.135367] [<ffffffff81174b91>] ? seccomp_phase1+0x1/0x230 [ 927.136523] [<ffffffff81061400>] kprobe_ftrace_handler+0xf0/0x150 [ 927.137666] [<ffffffff81174b95>] ? seccomp_phase1+0x5/0x230 [ 927.138802] [<ffffffff8117950c>] ftrace_ops_recurs_func+0x5c/0xb0 [ 927.139934] [<ffffffffa022b0d5>] 0xffffffffa022b0d5 [ 927.141066] [<ffffffff81174b91>] ? seccomp_phase1+0x1/0x230 [ 927.142199] [<ffffffff81174b95>] seccomp_phase1+0x5/0x230 [ 927.143323] [<ffffffff8102c0a4>] syscall_trace_enter_phase1+0xc4/0x150 [ 927.144450] [<ffffffff81174b95>] ? seccomp_phase1+0x5/0x230 [ 927.145572] [<ffffffff8102c0a4>] ? syscall_trace_enter_phase1+0xc4/0x150 [ 927.146666] [<ffffffff817f9a9f>] tracesys+0xd/0x44 [ 927.147723] Code: 48 8b 46 10 48 39 d0 76 2c 8b 85 fc fd ff ff 83 f8 20 77 21 83 c0 01 89 85 fc fd ff ff 48 8d 44 d6 80 48 8b 00 48 83 f8 00 74 0a <48> 8b 40 20 48 83 c0 33 ff e0 48 89 d8 48 8b 9d d8 fd ff ff 4c [ 927.150046] RIP [<ffffffffa002440d>] 0xffffffffa002440d The code section with the instructions that traps points into the eBPF JIT image of the root program (the one invoking the tail call instruction). Using bpf_jit_disasm -o on the eBPF root program image: [...] 4e: mov -0x204(%rbp),%eax 8b 85 fc fd ff ff 54: cmp $0x20,%eax <--- if (tail_call_cnt > MAX_TAIL_CALL_CNT) 83 f8 20 57: ja 0x000000000000007a 77 21 59: add $0x1,%eax <--- tail_call_cnt++ 83 c0 01 5c: mov %eax,-0x204(%rbp) 89 85 fc fd ff ff 62: lea -0x80(%rsi,%rdx,8),%rax <--- prog = array->prog[index] 48 8d 44 d6 80 67: mov (%rax),%rax 48 8b 00 6a: cmp $0x0,%rax <--- check for NULL 48 83 f8 00 6e: je 0x000000000000007a 74 0a 70: mov 0x20(%rax),%rax <--- GPF triggered here! fetch of bpf_func 48 8b 40 20 [ matches <48> 8b 40 20 ... from above ] 74: add $0x33,%rax <--- prologue skip of new prog 48 83 c0 33 78: jmpq *%rax <--- jump to new prog insns ff e0 [...] The problem is that rax has 5a5a5a5a5a5a5a5a, which suggests a tail call jump to map slot 0 is pointing to a poisoned page. The issue is the following: lea instruction has a wrong offset, i.e. it should be ... lea 0x80(%rsi,%rdx,8),%rax ... but it actually seems to be ... lea -0x80(%rsi,%rdx,8),%rax ... where 0x80 is offsetof(struct bpf_array, prog), thus the offset needs to be positive instead of negative. Disassembling the interpreter, we btw similarly do: [...] c88: lea 0x80(%rax,%rdx,8),%rax <--- prog = array->prog[index] 48 8d 84 d0 80 00 00 00 c90: add $0x1,%r13d 41 83 c5 01 c94: mov (%rax),%rax 48 8b 00 [...] Now the other interesting fact is that this panic triggers only when things like CONFIG_LOCKDEP are being used. In that case offsetof(struct bpf_array, prog) starts at offset 0x80 and in non-CONFIG_LOCKDEP case at offset 0x50. Reason is that the work_struct inside struct bpf_map grows by 48 bytes in my case due to the lockdep_map member (which also has CONFIG_LOCK_STAT enabled members). Changing the emitter to always use the 4 byte displacement in the lea instruction fixes the panic on my side. It increases the tail call instruction emission by 3 more byte, but it should cover us from various combinations (and perhaps other future increases on related structures). After patch, disassembly: [...] 9e: lea 0x80(%rsi,%rdx,8),%rax <--- CONFIG_LOCKDEP/CONFIG_LOCK_STAT 48 8d 84 d6 80 00 00 00 a6: mov (%rax),%rax 48 8b 00 [...] [...] 9e: lea 0x50(%rsi,%rdx,8),%rax <--- No CONFIG_LOCKDEP 48 8d 84 d6 50 00 00 00 a6: mov (%rax),%rax 48 8b 00 [...] Fixes: b52f00e6a715 ("x86: bpf_jit: implement bpf_tail_call() helper") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-26Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds1-0/+8
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fix from Thomas Gleixner: "A single fix for the intel cqm perf facility to prevent IPIs from interrupt context" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86/intel/cqm: Return cached counter value from IRQ context
2015-07-26Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds6-44/+32
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "This update contains: - the manual revert of the SYSCALL32 changes which caused a regression - a fix for the MPX vma handling - three fixes for the ioremap 'is ram' checks. - PAT warning fixes - a trivial fix for the size calculation of TLB tracepoints - handle old EFI structures gracefully This also contains a PAT fix from Jan plus a revert thereof. Toshi explained why the code is correct" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm/pat: Revert 'Adjust default caching mode translation tables' x86/asm/entry/32: Revert 'Do not use R9 in SYSCALL32' commit x86/mm: Fix newly introduced printk format warnings mm: Fix bugs in region_is_ram() x86/mm: Remove region_is_ram() call from ioremap x86/mm: Move warning from __ioremap_check_ram() to the call site x86/mm/pat, drivers/media/ivtv: Move the PAT warning and replace WARN() with pr_warn() x86/mm/pat, drivers/infiniband/ipath: Replace WARN() with pr_warn() x86/mm/pat: Adjust default caching mode translation tables x86/fpu: Disable dependent CPU features on "noxsave" x86/mpx: Do not set ->vm_ops on MPX VMAs x86/mm: Add parenthesis for TLB tracepoint size calculation efi: Handle memory error structures produced based on old versions of standard
2015-07-26x86/mm/pat: Revert 'Adjust default caching mode translation tables'Thomas Gleixner1-3/+3
Toshi explains: "No, the default values need to be set to the fallback types, i.e. minimal supported mode. For WC and WT, UC is the fallback type. When PAT is disabled, pat_init() does update the tables below to enable WT per the default BIOS setup. However, when PAT is enabled, but CPU has PAT -errata, WT falls back to UC per the default values." Revert: ca1fec58bc6a 'x86/mm/pat: Adjust default caching mode translation tables' Requested-by: Toshi Kani <toshi.kani@hp.com> Cc: Jan Beulich <jbeulich@suse.de> Link: http://lkml.kernel.org/r/1437577776.3214.252.camel@hp.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-26perf/x86/intel/cqm: Return cached counter value from IRQ contextMatt Fleming1-0/+8
Peter reported the following potential crash which I was able to reproduce with his test program, [ 148.765788] ------------[ cut here ]------------ [ 148.765796] WARNING: CPU: 34 PID: 2840 at kernel/smp.c:417 smp_call_function_many+0xb6/0x260() [ 148.765797] Modules linked in: [ 148.765800] CPU: 34 PID: 2840 Comm: perf Not tainted 4.2.0-rc1+ #4 [ 148.765803] ffffffff81cdc398 ffff88085f105950 ffffffff818bdfd5 0000000000000007 [ 148.765805] 0000000000000000 ffff88085f105990 ffffffff810e413a 0000000000000000 [ 148.765807] ffffffff82301080 0000000000000022 ffffffff8107f640 ffffffff8107f640 [ 148.765809] Call Trace: [ 148.765810] <NMI> [<ffffffff818bdfd5>] dump_stack+0x45/0x57 [ 148.765818] [<ffffffff810e413a>] warn_slowpath_common+0x8a/0xc0 [ 148.765822] [<ffffffff8107f640>] ? intel_cqm_stable+0x60/0x60 [ 148.765824] [<ffffffff8107f640>] ? intel_cqm_stable+0x60/0x60 [ 148.765825] [<ffffffff810e422a>] warn_slowpath_null+0x1a/0x20 [ 148.765827] [<ffffffff811613f6>] smp_call_function_many+0xb6/0x260 [ 148.765829] [<ffffffff8107f640>] ? intel_cqm_stable+0x60/0x60 [ 148.765831] [<ffffffff81161748>] on_each_cpu_mask+0x28/0x60 [ 148.765832] [<ffffffff8107f6ef>] intel_cqm_event_count+0x7f/0xe0 [ 148.765836] [<ffffffff811cdd35>] perf_output_read+0x2a5/0x400 [ 148.765839] [<ffffffff811d2e5a>] perf_output_sample+0x31a/0x590 [ 148.765840] [<ffffffff811d333d>] ? perf_prepare_sample+0x26d/0x380 [ 148.765841] [<ffffffff811d3497>] perf_event_output+0x47/0x60 [ 148.765843] [<ffffffff811d36c5>] __perf_event_overflow+0x215/0x240 [ 148.765844] [<ffffffff811d4124>] perf_event_overflow+0x14/0x20 [ 148.765847] [<ffffffff8107e7f4>] intel_pmu_handle_irq+0x1d4/0x440 [ 148.765849] [<ffffffff811d07a6>] ? __perf_event_task_sched_in+0x36/0xa0 [ 148.765853] [<ffffffff81219bad>] ? vunmap_page_range+0x19d/0x2f0 [ 148.765854] [<ffffffff81219d11>] ? unmap_kernel_range_noflush+0x11/0x20 [ 148.765859] [<ffffffff814ce6fe>] ? ghes_copy_tofrom_phys+0x11e/0x2a0 [ 148.765863] [<ffffffff8109e5db>] ? native_apic_msr_write+0x2b/0x30 [ 148.765865] [<ffffffff8109e44d>] ? x2apic_send_IPI_self+0x1d/0x20 [ 148.765869] [<ffffffff81065135>] ? arch_irq_work_raise+0x35/0x40 [ 148.765872] [<ffffffff811c8d86>] ? irq_work_queue+0x66/0x80 [ 148.765875] [<ffffffff81075306>] perf_event_nmi_handler+0x26/0x40 [ 148.765877] [<ffffffff81063ed9>] nmi_handle+0x79/0x100 [ 148.765879] [<ffffffff81064422>] default_do_nmi+0x42/0x100 [ 148.765880] [<ffffffff81064563>] do_nmi+0x83/0xb0 [ 148.765884] [<ffffffff818c7c0f>] end_repeat_nmi+0x1e/0x2e [ 148.765886] [<ffffffff811d07a6>] ? __perf_event_task_sched_in+0x36/0xa0 [ 148.765888] [<ffffffff811d07a6>] ? __perf_event_task_sched_in+0x36/0xa0 [ 148.765890] [<ffffffff811d07a6>] ? __perf_event_task_sched_in+0x36/0xa0 [ 148.765891] <<EOE>> [<ffffffff8110ab66>] finish_task_switch+0x156/0x210 [ 148.765898] [<ffffffff818c1671>] __schedule+0x341/0x920 [ 148.765899] [<ffffffff818c1c87>] schedule+0x37/0x80 [ 148.765903] [<ffffffff810ae1af>] ? do_page_fault+0x2f/0x80 [ 148.765905] [<ffffffff818c1f4a>] schedule_user+0x1a/0x50 [ 148.765907] [<ffffffff818c666c>] retint_careful+0x14/0x32 [ 148.765908] ---[ end trace e33ff2be78e14901 ]--- The CQM task events are not safe to be called from within interrupt context because they require performing an IPI to read the counter value on all sockets. And performing IPIs from within IRQ context is a "no-no". Make do with the last read counter value currently event in event->count when we're invoked in this context. Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vikas Shivappa <vikas.shivappa@intel.com> Cc: Kanaka Juvva <kanaka.d.juvva@intel.com> Cc: Will Auld <will.auld@intel.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/1437490509-15373-1-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-24x86/asm/entry/32: Revert 'Do not use R9 in SYSCALL32' commitDenys Vlasenko1-5/+9
This change reverts most of commit 53e9accf0f 'Do not use R9 in SYSCALL32'. I don't yet understand how, but code in that commit sometimes fails to preserve EBP. See https://bugzilla.kernel.org/show_bug.cgi?id=101061 "Problems while executing 32-bit code on AMD64" Reported-and-tested-by: Krzysztof A. Sobiecki <sobkas@gmail.com> Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Will Drewry <wad@chromium.org> Cc: Kees Cook <keescook@chromium.org> CC: x86@kernel.org Link: http://lkml.kernel.org/r/1437740203-11552-1-git-send-email-dvlasenk@redhat.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-24x86/mm: Fix newly introduced printk format warningsThomas Gleixner1-2/+2
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-23KVM: x86: rename quirk constants to KVM_X86_QUIRK_*Paolo Bonzini4-5/+5
Make them clearly architecture-dependent; the capability is valid for all architectures, but the argument is not. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-23KVM: vmx: obey KVM_QUIRK_CD_NW_CLEAREDXiao Guangrong1-1/+4
OVMF depends on WB to boot fast, because it only clears caches after it has set up MTRRs---which is too late. Let's do writeback if CR0.CD is set to make it happy, similar to what SVM is already doing. Signed-off-by: Xiao Guangrong <guangrong.xiao@intel.com> Tested-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-23KVM: x86: introduce kvm_check_has_quirkPaolo Bonzini3-2/+7
The logic of the disabled_quirks field usually results in a double negation. Wrap it in a simple function that checks the bit and negates it. Based on a patch from Xiao Guangrong. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-23KVM: MTRR: simplify kvm_mtrr_get_guest_memory_typeXiao Guangrong1-9/+10
kvm_mtrr_get_guest_memory_type never returns -1 which is implied in the current code since if @type = -1 (means no MTRR contains the range), iter.partial_map must be true Simplify the code to indicate this fact Signed-off-by: Xiao Guangrong <guangrong.xiao@intel.com> Tested-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-23KVM: MTRR: fix memory type handling if MTRR is completely disabledXiao Guangrong1-1/+20
Currently code uses default memory type if MTRR is fully disabled, fix it by using UC instead. Signed-off-by: Xiao Guangrong <guangrong.xiao@intel.com> Tested-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-22x86/mm: Remove region_is_ram() call from ioremapToshi Kani1-18/+6
__ioremap_caller() calls region_is_ram() to walk through the iomem_resource table to check if a target range is in RAM, which was added to improve the lookup performance over page_is_ram() (commit 906e36c5c717 "x86: use optimized ioresource lookup in ioremap function"). page_is_ram() was no longer used when this change was added, though. __ioremap_caller() then calls walk_system_ram_range(), which had replaced page_is_ram() to improve the lookup performance (commit c81c8a1eeede "x86, ioremap: Speed up check for RAM pages"). Since both checks walk through the same iomem_resource table for the same purpose, there is no need to call both functions. Aside of that walk_system_ram_range() is the only useful check at the moment because region_is_ram() always returns -1 due to an implementation bug. That bug in region_is_ram() cannot be fixed without breaking existing ioremap callers, which rely on the subtle difference of walk_system_ram_range() versus non page aligned ranges. Once these offending callers are fixed we can use region_is_ram() and remove walk_system_ram_range(). [ tglx: Massaged changelog ] Signed-off-by: Toshi Kani <toshi.kani@hp.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Cc: Roland Dreier <roland@purestorage.com> Cc: Mike Travis <travis@sgi.com> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/1437088996-28511-3-git-send-email-toshi.kani@hp.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-22x86/mm: Move warning from __ioremap_check_ram() to the call siteToshi Kani1-3/+4
__ioremap_check_ram() has a WARN_ONCE() which is emitted when the given pfn range is not RAM. The warning is bogus in two aspects: - it never triggers since walk_system_ram_range() only calls __ioremap_check_ram() for RAM ranges. - the warning message is wrong as it says: "ioremap on RAM' after it established that the pfn range is not RAM. Move the WARN_ONCE() to __ioremap_caller(), and update the message to include the address range so we get an actual warning when something tries to ioremap system RAM. [ tglx: Massaged changelog ] Signed-off-by: Toshi Kani <toshi.kani@hp.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Cc: Roland Dreier <roland@purestorage.com> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/1437088996-28511-2-git-send-email-toshi.kani@hp.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-21x86/mm/pat: Adjust default caching mode translation tablesJan Beulich1-3/+3
Make WT really mean WT (rather than UC). I can't see why commit 9cd25aac1f ("x86/mm/pat: Emulate PAT when it is disabled") didn't make this to match its changes to pat_init(). Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Link: http://lkml.kernel.org/r/55ACC3660200007800092E62@mail.emea.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-21x86/fpu: Disable dependent CPU features on "noxsave"Jan Beulich1-0/+6
Complete the set of dependent features that need disabling at once: XSAVEC, AVX-512 and all currently known to the kernel extensions to it, as well as MPX need to be disabled too. Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Dave Hansen <dave.hansen@linux.intel.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/55ACC40D0200007800092E6C@mail.emea.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-21x86/mpx: Do not set ->vm_ops on MPX VMAsKirill A. Shutemov2-21/+10
MPX setups private anonymous mapping, but uses vma->vm_ops too. This can confuse core VM, as it relies on vm->vm_ops to distinguish file VMAs from anonymous. As result we will get SIGBUS, because handle_pte_fault() thinks it's file VMA without vm_ops->fault and it doesn't know how to handle the situation properly. Let's fix that by not setting ->vm_ops. We don't really need ->vm_ops here: MPX VMA can be detected with VM_MPX flag. And vma_merge() will not merge MPX VMA with non-MPX VMA, because ->vm_flags won't match. The only thing left is name of VMA. I'm not sure if it's part of ABI, or we can just drop it. The patch keep it by providing arch_vma_name() on x86. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: <stable@vger.kernel.org> # Fixes: 6b7339f4 (mm: avoid setting up anonymous pages into file mapping) Cc: Andy Lutomirski <luto@amacapital.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dave@sr71.net Link: http://lkml.kernel.org/r/20150720212958.305CC3E9@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-21x86/mm: Add parenthesis for TLB tracepoint size calculationDave Hansen1-1/+1
flush_tlb_info->flush_start/end are both normal virtual addresses. When calculating 'nr_pages' (only used for the tracepoint), I neglected to put parenthesis in. Thanks to David Koufaty for pointing this out. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dave@sr71.net Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20150720230153.9E834081@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-18Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds8-209/+350
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "Two families of fixes: - Fix an FPU context related boot crash on newer x86 hardware with larger context sizes than what most people test. To fix this without ugly kludges or extensive reverts we had to touch core task allocator, to allow x86 to determine the task size dynamically, at boot time. I've tested it on a number of x86 platforms, and I cross-built it to a handful of architectures: (warns) (warns) testing x86-64: -git: pass ( 0), -tip: pass ( 0) testing x86-32: -git: pass ( 0), -tip: pass ( 0) testing arm: -git: pass ( 1359), -tip: pass ( 1359) testing cris: -git: pass ( 1031), -tip: pass ( 1031) testing m32r: -git: pass ( 1135), -tip: pass ( 1135) testing m68k: -git: pass ( 1471), -tip: pass ( 1471) testing mips: -git: pass ( 1162), -tip: pass ( 1162) testing mn10300: -git: pass ( 1058), -tip: pass ( 1058) testing parisc: -git: pass ( 1846), -tip: pass ( 1846) testing sparc: -git: pass ( 1185), -tip: pass ( 1185) ... so I hope the cross-arch impact 'none', as intended. (by Dave Hansen) - Fix various NMI handling related bugs unearthed by the big asm code rewrite and generally make the NMI code more robust and more maintainable while at it. These changes are a bit late in the cycle, I hope they are still acceptable. (by Andy Lutomirski)" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/fpu, sched: Introduce CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT and use it on x86 x86/fpu, sched: Dynamically allocate 'struct fpu' x86/entry/64, x86/nmi/64: Add CONFIG_DEBUG_ENTRY NMI testing code x86/nmi/64: Make the "NMI executing" variable more consistent x86/nmi/64: Minor asm simplification x86/nmi/64: Use DF to avoid userspace RSP confusing nested NMI detection x86/nmi/64: Reorder nested NMI checks x86/nmi/64: Improve nested NMI comments x86/nmi/64: Switch stacks on userspace NMI entry x86/nmi/64: Remove asm code that saves CR2 x86/nmi: Enable nested do_nmi() handling for 64-bit kernels
2015-07-18Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "Mostly tooling fixes, plus a static key fix fixing /sys/devices/cpu/rdpmc" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf tools: Really allow to specify custom CC, AR or LD perf auxtrace: Fix misplaced check for HAVE_SYNC_COMPARE_AND_SWAP_SUPPORT perf hists browser: Take the --comm, --dsos, etc filters into account perf symbols: Store if there is a filter in place x86, perf: Fix static_key bug in load_mm_cr4() tools: Copy lib/hweight.c from the kernel sources perf tools: Fix the detached tarball wrt rbtree copy perf thread_map: Fix the sizeof() calculation for map entries tools lib: Improve clean target perf stat: Fix shadow declaration of close perf tools: Fix lockup using 32-bit compat vdso
2015-07-18Merge branch 'irq-urgent-for-linus' of ↵Linus Torvalds1-0/+11
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq fixes from Ingo Molnar: "Misc irq fixes: - two driver fixes - a Xen regression fix - a nested irq thread crash fix" * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: irqchip/gicv3-its: Fix mapping of LPIs to collections genirq: Prevent resend to interrupts marked IRQ_NESTED_THREAD genirq: Revert sparse irq locking around __cpu_up() and move it to x86 for now gpio/davinci: Fix race in installing chained irq handler
2015-07-18x86/fpu, sched: Introduce CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT and use it ↵Ingo Molnar3-9/+11
on x86 Don't burden architectures without dynamic task_struct sizing with the overhead of dynamic sizing. Also optimize the x86 code a bit by caching task_struct_size. Acked-and-Tested-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.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> Link: http://lkml.kernel.org/r/1437128892-9831-3-git-send-email-mingo@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-18x86/fpu, sched: Dynamically allocate 'struct fpu'Dave Hansen4-38/+85
The FPU rewrite removed the dynamic allocations of 'struct fpu'. But, this potentially wastes massive amounts of memory (2k per task on systems that do not have AVX-512 for instance). Instead of having a separate slab, this patch just appends the space that we need to the 'task_struct' which we dynamically allocate already. This saves from doing an extra slab allocation at fork(). The only real downside here is that we have to stick everything and the end of the task_struct. But, I think the BUILD_BUG_ON()s I stuck in there should keep that from being too fragile. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> 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> Link: http://lkml.kernel.org/r/1437128892-9831-2-git-send-email-mingo@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-18mm: clean up per architecture MM hook header filesLaurent Dufour2-15/+1
Commit 2ae416b142b6 ("mm: new mm hook framework") introduced an empty header file (mm-arch-hooks.h) for every architecture, even those which doesn't need to define mm hooks. As suggested by Geert Uytterhoeven, this could be cleaned through the use of a generic header file included via each per architecture asm/include/Kbuild file. The PowerPC architecture is not impacted here since this architecture has to defined the arch_remap MM hook. Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com> Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Vineet Gupta <vgupta@synopsys.com> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-17x86/entry/64, x86/nmi/64: Add CONFIG_DEBUG_ENTRY NMI testing codeAndy Lutomirski2-0/+27
It turns out to be rather tedious to test the NMI nesting code. Make it easier: add a new CONFIG_DEBUG_ENTRY option that causes the NMI handler to pre-emptively unmask NMIs. With this option set, errors in the repeat_nmi logic or failures to detect that we're in a nested NMI will result in quick panics under perf (especially if multiple counters are running at high frequency) instead of requiring an unusual workload that generates page faults or breakpoints inside NMIs. I called it CONFIG_DEBUG_ENTRY instead of CONFIG_DEBUG_NMI_ENTRY because I want to add new non-NMI checks elsewhere in the entry code in the future, and I'd rather not add too many new config options or add this option and then immediately rename it. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Cc: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-17x86/nmi/64: Make the "NMI executing" variable more consistentAndy Lutomirski1-6/+5
Currently, "NMI executing" is one the first time an outermost NMI hits repeat_nmi and zero thereafter. Change it to be zero each time for consistency. This is intended to help NMI handling fail harder if it's buggy. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Cc: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-17x86/nmi/64: Minor asm simplificationAndy Lutomirski1-2/+1
Replace LEA; MOV with an equivalent SUB. This saves one instruction. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Cc: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-17x86/nmi/64: Use DF to avoid userspace RSP confusing nested NMI detectionAndy Lutomirski1-4/+25
We have a tricky bug in the nested NMI code: if we see RSP pointing to the NMI stack on NMI entry from kernel mode, we assume that we are executing a nested NMI. This isn't quite true. A malicious userspace program can point RSP at the NMI stack, issue SYSCALL, and arrange for an NMI to happen while RSP is still pointing at the NMI stack. Fix it with a sneaky trick. Set DF in the region of code that the RSP check is intended to detect. IRET will clear DF atomically. ( Note: other than paravirt, there's little need for all this complexity. We could check RIP instead of RSP. ) Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Cc: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-17x86/nmi/64: Reorder nested NMI checksAndy Lutomirski1-16/+18
Check the repeat_nmi .. end_repeat_nmi special case first. The next patch will rework the RSP check and, as a side effect, the RSP check will no longer detect repeat_nmi .. end_repeat_nmi, so we'll need this ordering of the checks. Note: this is more subtle than it appears. The check for repeat_nmi .. end_repeat_nmi jumps straight out of the NMI code instead of adjusting the "iret" frame to force a repeat. This is necessary, because the code between repeat_nmi and end_repeat_nmi sets "NMI executing" and then writes to the "iret" frame itself. If a nested NMI comes in and modifies the "iret" frame while repeat_nmi is also modifying it, we'll end up with garbage. The old code got this right, as does the new code, but the new code is a bit more explicit. If we were to move the check right after the "NMI executing" check, then we'd get it wrong and have random crashes. ( Because the "NMI executing" check would jump to the code that would modify the "iret" frame without checking if the interrupted NMI was currently modifying it. ) Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Cc: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-17x86/nmi/64: Improve nested NMI commentsAndy Lutomirski2-68/+94
I found the nested NMI documentation to be difficult to follow. Improve the comments. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Cc: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-17x86/nmi/64: Switch stacks on userspace NMI entryAndy Lutomirski1-4/+58
Returning to userspace is tricky: IRET can fail, and ESPFIX can rearrange the stack prior to IRET. The NMI nesting fixup relies on a precise stack layout and atomic IRET. Rather than trying to teach the NMI nesting fixup to handle ESPFIX and failed IRET, punt: run NMIs that came from user mode on the normal kernel stack. This will make some nested NMIs visible to C code, but the C code is okay with that. As a side effect, this should speed up perf: it eliminates an RDMSR when NMIs come from user mode. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Reviewed-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> Cc: stable@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-17x86/nmi/64: Remove asm code that saves CR2Andy Lutomirski1-17/+0
Now that do_nmi saves CR2, we don't need to save it in asm. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Acked-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> Cc: stable@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-17x86/nmi: Enable nested do_nmi() handling for 64-bit kernelsAndy Lutomirski1-71/+52
32-bit kernels handle nested NMIs in C. Enable the exact same handling on 64-bit kernels as well. This isn't currently necessary, but it will become necessary once the asm code starts allowing limited nesting. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Cc: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-17Merge tag 'platform-drivers-x86-v4.2-3' of ↵Linus Torvalds1-27/+0
git://git.infradead.org/users/dvhart/linux-platform-drivers-x86 Pull x86 platform driver fixes from Darren Hart: "Fix SMBIOS call handling and hwswitch state coherency in the dell-laptop driver. Cleanups for intel_*_ipc drivers. Details: dell-laptop: - Do not cache hwswitch state - Check return value of each SMBIOS call - Clear buffer before each SMBIOS call intel_scu_ipc: - Move local memory initialization out of a mutex intel_pmc_ipc: - Update kerneldoc formatting - Fix compiler casting warnings" * tag 'platform-drivers-x86-v4.2-3' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86: intel_scu_ipc: move local memory initialization out of a mutex intel_pmc_ipc: Update kerneldoc formatting dell-laptop: Do not cache hwswitch state dell-laptop: Check return value of each SMBIOS call dell-laptop: Clear buffer before each SMBIOS call intel_pmc_ipc: Fix compiler casting warnings
2015-07-15Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds8-21/+142
Pull KVM fixes from Paolo Bonzini: - Fix FPU refactoring ("kvm: x86: fix load xsave feature warning") - Fix eager FPU mode (Cc stable) - AMD bits of MTRR virtualization * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: kvm: x86: fix load xsave feature warning KVM: x86: apply guest MTRR virtualization on host reserved pages KVM: SVM: Sync g_pat with guest-written PAT value KVM: SVM: use NPT page attributes KVM: count number of assigned devices KVM: VMX: fix vmwrite to invalid VMCS KVM: x86: reintroduce kvm_is_mmio_pfn x86: hyperv: add CPUID bit for crash handlers
2015-07-15genirq: Revert sparse irq locking around __cpu_up() and move it to x86 for nowThomas Gleixner1-0/+11
Boris reported that the sparse_irq protection around __cpu_up() in the generic code causes a regression on Xen. Xen allocates interrupts and some more in the xen_cpu_up() function, so it deadlocks on the sparse_irq_lock. There is no simple fix for this and we really should have the protection for all architectures, but for now the only solution is to move it to x86 where actual wreckage due to the lack of protection has been observed. Reported-and-tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Fixes: a89941816726 'hotplug: Prevent alloc/free of irq descriptors during cpu up/down' Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: xiao jin <jin.xiao@intel.com> Cc: Joerg Roedel <jroedel@suse.de> Cc: Borislav Petkov <bp@suse.de> Cc: Yanmin Zhang <yanmin_zhang@linux.intel.com> Cc: xen-devel <xen-devel@lists.xenproject.org>
2015-07-12Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds12-87/+116
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: - the high latency PIT detection fix, which slipped through the cracks for rc1 - a regression fix for the early printk mechanism - the x86 part to plug irq/vector related hotplug races - move the allocation of the espfix pages on cpu hotplug to non atomic context. The current code triggers a might_sleep() warning. - a series of KASAN fixes addressing boot crashes and usability - a trivial typo fix for Kconfig help text * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/kconfig: Fix typo in the CONFIG_CMDLINE_BOOL help text x86/irq: Retrieve irq data after locking irq_desc x86/irq: Use proper locking in check_irq_vectors_for_cpu_disable() x86/irq: Plug irq vector hotplug race x86/earlyprintk: Allow early_printk() to use console style parameters like '115200n8' x86/espfix: Init espfix on the boot CPU side x86/espfix: Add 'cpu' parameter to init_espfix_ap() x86/kasan: Move KASAN_SHADOW_OFFSET to the arch Kconfig x86/kasan: Add message about KASAN being initialized x86/kasan: Fix boot crash on AMD processors x86/kasan: Flush TLBs after switching CR3 x86/kasan: Fix KASAN shadow region page tables x86/init: Clear 'init_level4_pgt' earlier x86/tsc: Let high latency PIT fail fast in quick_pit_calibrate()
2015-07-10kvm: x86: fix load xsave feature warningWanpeng Li1-2/+1
[ 68.196974] WARNING: CPU: 1 PID: 2140 at arch/x86/kvm/x86.c:3161 kvm_arch_vcpu_ioctl+0xe88/0x1340 [kvm]() [ 68.196975] Modules linked in: snd_hda_codec_hdmi i915 rfcomm bnep bluetooth i2c_algo_bit rfkill nfsd drm_kms_helper nfs_acl nfs drm lockd grace sunrpc fscache snd_hda_codec_realtek snd_hda_codec_generic snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep snd_pcm snd_seq_dummy snd_seq_oss x86_pkg_temp_thermal snd_seq_midi kvm_intel snd_seq_midi_event snd_rawmidi kvm snd_seq ghash_clmulni_intel fuse snd_timer aesni_intel parport_pc ablk_helper snd_seq_device cryptd ppdev snd lp parport lrw dcdbas gf128mul i2c_core glue_helper lpc_ich video shpchp mfd_core soundcore serio_raw acpi_cpufreq ext4 mbcache jbd2 sd_mod crc32c_intel ahci libahci libata e1000e ptp pps_core [ 68.197005] CPU: 1 PID: 2140 Comm: qemu-system-x86 Not tainted 4.2.0-rc1+ #2 [ 68.197006] Hardware name: Dell Inc. OptiPlex 7020/0F5C5X, BIOS A03 01/08/2015 [ 68.197007] ffffffffa03b0657 ffff8800d984bca8 ffffffff815915a2 0000000000000000 [ 68.197009] 0000000000000000 ffff8800d984bce8 ffffffff81057c0a 00007ff6d0001000 [ 68.197010] 0000000000000002 ffff880211c1a000 0000000000000004 ffff8800ce0288c0 [ 68.197012] Call Trace: [ 68.197017] [<ffffffff815915a2>] dump_stack+0x45/0x57 [ 68.197020] [<ffffffff81057c0a>] warn_slowpath_common+0x8a/0xc0 [ 68.197022] [<ffffffff81057cfa>] warn_slowpath_null+0x1a/0x20 [ 68.197029] [<ffffffffa037bed8>] kvm_arch_vcpu_ioctl+0xe88/0x1340 [kvm] [ 68.197035] [<ffffffffa037aede>] ? kvm_arch_vcpu_load+0x4e/0x1c0 [kvm] [ 68.197040] [<ffffffffa03696a6>] kvm_vcpu_ioctl+0xc6/0x5c0 [kvm] [ 68.197043] [<ffffffff811252d2>] ? perf_pmu_enable+0x22/0x30 [ 68.197044] [<ffffffff8112663e>] ? perf_event_context_sched_in+0x7e/0xb0 [ 68.197048] [<ffffffff811a6882>] do_vfs_ioctl+0x2c2/0x4a0 [ 68.197050] [<ffffffff8107bf33>] ? finish_task_switch+0x173/0x220 [ 68.197053] [<ffffffff8123307f>] ? selinux_file_ioctl+0x4f/0xd0 [ 68.197055] [<ffffffff8122cac3>] ? security_file_ioctl+0x43/0x60 [ 68.197057] [<ffffffff811a6ad9>] SyS_ioctl+0x79/0x90 [ 68.197060] [<ffffffff81597e57>] entry_SYSCALL_64_fastpath+0x12/0x6a [ 68.197061] ---[ end trace 558a5ebf9445fc80 ]--- After commit (0c4109bec0 'x86/fpu/xstate: Fix up bad get_xsave_addr() assumptions'), there is no assumption an xsave bit is present in the hardware (pcntxt_mask) that it is always present in a given xsave buffer. An enabled state to be present on 'pcntxt_mask', but *not* in 'xstate_bv' could happen when the last 'xsave' did not request that this feature be saved (unlikely) or because the "init optimization" caused it to not be saved. This patch kill the assumption. Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-10KVM: x86: apply guest MTRR virtualization on host reserved pagesPaolo Bonzini2-13/+5
Currently guest MTRR is avoided if kvm_is_reserved_pfn returns true. However, the guest could prefer a different page type than UC for such pages. A good example is that pass-throughed VGA frame buffer is not always UC as host expected. This patch enables full use of virtual guest MTRRs. Suggested-by: Xiao Guangrong <guangrong.xiao@linux.intel.com> Tested-by: Joerg Roedel <jroedel@suse.de> (on AMD) Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-10KVM: SVM: Sync g_pat with guest-written PAT valueJan Kiszka1-0/+10
When hardware supports the g_pat VMCB field, we can use it for emulating the PAT configuration that the guest configures by writing to the corresponding MSR. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Tested-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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