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2020-11-07x86/platform/uv: Remove spaces from OEM IDsMike Travis1-0/+3
Testing shows that trailing spaces caused problems with the OEM_ID and the OEM_TABLE_ID. One being that the OEM_ID would not string compare correctly. Another the OEM_ID and OEM_TABLE_ID would be concatenated in the printout. Remove any trailing spaces. Fixes: 1e61f5a95f191 ("Add and decode Arch Type in UVsystab") Signed-off-by: Mike Travis <mike.travis@hpe.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201105222741.157029-3-mike.travis@hpe.com
2020-11-07x86/platform/uv: Fix missing OEM_TABLE_IDMike Travis1-2/+5
Testing shows a problem in that the OEM_TABLE_ID was missing for hubless systems. This is used to determine the APIC type (legacy or extended). Add the OEM_TABLE_ID to the early hubless processing. Fixes: 1e61f5a95f191 ("Add and decode Arch Type in UVsystab") Signed-off-by: Mike Travis <mike.travis@hpe.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201105222741.157029-2-mike.travis@hpe.com
2020-11-07x86/cpu: Avoid cpuinfo-induced IPIing of idle CPUsPaul E. McKenney1-0/+6
Currently, accessing /proc/cpuinfo sends IPIs to idle CPUs in order to learn their clock frequency. Which is a bit strange, given that waking them from idle likely significantly changes their clock frequency. This commit therefore avoids sending /proc/cpuinfo-induced IPIs to idle CPUs. [ paulmck: Also check for idle in arch_freq_prepare_all(). ] Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: <x86@kernel.org>
2020-11-07x86/cpu: Avoid cpuinfo-induced IPI pileupsPaul E. McKenney1-1/+9
The aperfmperf_snapshot_cpu() function is invoked upon access to /proc/cpuinfo, and it does do an early exit if the specified CPU has recently done a snapshot. Unfortunately, the indication that a snapshot has been completed is set in an IPI handler, and the execution of this handler can be delayed by any number of unfortunate events. This means that a system that starts a number of applications, each of which parses /proc/cpuinfo, can suffer from an smp_call_function_single() storm, especially given that each access to /proc/cpuinfo invokes smp_call_function_single() for all CPUs. Please note that this is not theoretical speculation. Note also that one CPU's pending IPI serves all requests, so there is no point in ever having more than one IPI pending to a given CPU. This commit therefore suppresses duplicate IPIs to a given CPU via a new ->scfpending field in the aperfmperf_sample structure. This field is set to the value one if an IPI is pending to the corresponding CPU and to zero otherwise. The aperfmperf_snapshot_cpu() function uses atomic_xchg() to set this field to the value one and sample the old value. If this function's "wait" parameter is zero, smp_call_function_single() is called only if the old value of the ->scfpending field was zero. The IPI handler uses atomic_set_release() to set this new field to zero just before returning, so that the prior stores into the aperfmperf_sample structure are seen by future requests that get to the atomic_xchg(). Future requests that pass the elapsed-time check are ordered by the fact that on x86 loads act as acquire loads, just as was the case prior to this change. The return value is based off of the age of the prior snapshot, just as before. Reported-by: Dave Jones <davej@codemonkey.org.uk> [ paulmck: Allow /proc/cpuinfo to take advantage of arch_freq_get_on_cpu(). ] [ paulmck: Add comment on memory barrier. ] Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: <x86@kernel.org>
2020-11-06x86/mce: Correct the detection of invalid notifier prioritiesZhen Lei1-1/+2
Commit c9c6d216ed28 ("x86/mce: Rename "first" function as "early"") changed the enumeration of MCE notifier priorities. Correct the check for notifier priorities to cover the new range. [ bp: Rewrite commit message, remove superfluous brackets in conditional. ] Fixes: c9c6d216ed28 ("x86/mce: Rename "first" function as "early"") Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20201106141216.2062-2-thunder.leizhen@huawei.com
2020-11-06ftrace: Add recording of functions that caused recursionSteven Rostedt (VMware)1-1/+1
This adds CONFIG_FTRACE_RECORD_RECURSION that will record to a file "recursed_functions" all the functions that caused recursion while a callback to the function tracer was running. Link: https://lkml.kernel.org/r/20201106023548.102375687@goodmis.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Guo Ren <guoren@kernel.org> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Helge Deller <deller@gmx.de> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@alien8.de> Cc: x86@kernel.org Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: Miroslav Benes <mbenes@suse.cz> Cc: Petr Mladek <pmladek@suse.com> Cc: Joe Lawrence <joe.lawrence@redhat.com> Cc: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-csky@vger.kernel.org Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-s390@vger.kernel.org Cc: live-patching@vger.kernel.org Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-11-06kprobes/ftrace: Add recursion protection to the ftrace callbackSteven Rostedt (VMware)1-2/+10
If a ftrace callback does not supply its own recursion protection and does not set the RECURSION_SAFE flag in its ftrace_ops, then ftrace will make a helper trampoline to do so before calling the callback instead of just calling the callback directly. The default for ftrace_ops is going to change. It will expect that handlers provide their own recursion protection, unless its ftrace_ops states otherwise. Link: https://lkml.kernel.org/r/20201028115613.140212174@goodmis.org Link: https://lkml.kernel.org/r/20201106023546.944907560@goodmis.org Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: Miroslav Benes <mbenes@suse.cz> Cc: Petr Mladek <pmladek@suse.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Guo Ren <guoren@kernel.org> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Helge Deller <deller@gmx.de> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@alien8.de> Cc: x86@kernel.org Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: linux-csky@vger.kernel.org Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-s390@vger.kernel.org Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-11-06x86/mce: Assign boolean values to a bool variableKaixu Xia1-2/+2
Fix the following coccinelle warnings: ./arch/x86/kernel/cpu/mce/core.c:1765:3-20: WARNING: Assignment of 0/1 to bool variable ./arch/x86/kernel/cpu/mce/core.c:1584:2-9: WARNING: Assignment of 0/1 to bool variable [ bp: Massage commit message. ] Reported-by: Tosk Robot <tencent_os_robot@tencent.com> Signed-off-by: Kaixu Xia <kaixuxia@tencent.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/1604654363-1463-1-git-send-email-kaixuxia@tencent.com
2020-11-06ima: generalize x86/EFI arch glue for other EFI architecturesChester Lin2-96/+0
Move the x86 IMA arch code into security/integrity/ima/ima_efi.c, so that we will be able to wire it up for arm64 in a future patch. Co-developed-by: Chester Lin <clin@suse.com> Signed-off-by: Chester Lin <clin@suse.com> Acked-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-11-05x86/speculation: Allow IBPB to be conditionally enabled on CPUs with ↵Anand K Mistry1-18/+33
always-on STIBP On AMD CPUs which have the feature X86_FEATURE_AMD_STIBP_ALWAYS_ON, STIBP is set to on and spectre_v2_user_stibp == SPECTRE_V2_USER_STRICT_PREFERRED At the same time, IBPB can be set to conditional. However, this leads to the case where it's impossible to turn on IBPB for a process because in the PR_SPEC_DISABLE case in ib_prctl_set() the spectre_v2_user_stibp == SPECTRE_V2_USER_STRICT_PREFERRED condition leads to a return before the task flag is set. Similarly, ib_prctl_get() will return PR_SPEC_DISABLE even though IBPB is set to conditional. More generally, the following cases are possible: 1. STIBP = conditional && IBPB = on for spectre_v2_user=seccomp,ibpb 2. STIBP = on && IBPB = conditional for AMD CPUs with X86_FEATURE_AMD_STIBP_ALWAYS_ON The first case functions correctly today, but only because spectre_v2_user_ibpb isn't updated to reflect the IBPB mode. At a high level, this change does one thing. If either STIBP or IBPB is set to conditional, allow the prctl to change the task flag. Also, reflect that capability when querying the state. This isn't perfect since it doesn't take into account if only STIBP or IBPB is unconditionally on. But it allows the conditional feature to work as expected, without affecting the unconditional one. [ bp: Massage commit message and comment; space out statements for better readability. ] Fixes: 21998a351512 ("x86/speculation: Avoid force-disabling IBPB based on STIBP and enhanced IBRS.") Signed-off-by: Anand K Mistry <amistry@google.com> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lkml.kernel.org/r/20201105163246.v2.1.Ifd7243cd3e2c2206a893ad0a5b9a4f19549e22c6@changeid
2020-11-05x86/entry: Move nmi entry/exit into common codeThomas Gleixner3-12/+13
Lockdep state handling on NMI enter and exit is nothing specific to X86. It's not any different on other architectures. Also the extra state type is not necessary, irqentry_state_t can carry the necessary information as well. Move it to common code and extend irqentry_state_t to carry lockdep state. [ Ira: Make exit_rcu and lockdep a union as they are mutually exclusive between the IRQ and NMI exceptions, and add kernel documentation for struct irqentry_state_t ] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201102205320.1458656-7-ira.weiny@intel.com
2020-11-04Merge branch 'core/urgent' into core/entryThomas Gleixner77-1408/+4007
Pick up the entry fix before further modifications.
2020-11-04x86/ioapic: Use I/O-APIC ID for finding irqdomain, not indexDavid Woodhouse1-2/+2
In commit b643128b917 ("x86/ioapic: Use irq_find_matching_fwspec() to find remapping irqdomain") the I/O-APIC code was changed to find its parent irqdomain using irq_find_matching_fwspec(), but the key used for the lookup was wrong. It shouldn't use 'ioapic' which is the index into its own ioapics[] array. It should use the actual arbitration ID of the I/O-APIC in question, which is mpc_ioapic_id(ioapic). Fixes: b643128b917 ("x86/ioapic: Use irq_find_matching_fwspec() to find remapping irqdomain") Reported-by: lkp <oliver.sang@intel.com> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/57adf2c305cd0c5e9d860b2f3007a7e676fd0f9f.camel@infradead.org
2020-11-04x86/hyperv: Enable 15-bit APIC ID if the hypervisor supports itDexuan Cui1-0/+29
When a Linux VM runs on Hyper-V, if the VM has CPUs with >255 APIC IDs, the CPUs can't be the destination of IOAPIC interrupts, because the IOAPIC RTE's Dest Field has only 8 bits. Currently the hackery driver drivers/iommu/hyperv-iommu.c is used to ensure IOAPIC interrupts are only routed to CPUs that don't have >255 APIC IDs. However, there is an issue with kdump, because the kdump kernel can run on any CPU, and hence IOAPIC interrupts can't work if the kdump kernel run on a CPU with a >255 APIC ID. The kdump issue can be fixed by the Extended Dest ID, which is introduced recently by David Woodhouse (for IOAPIC, see the field virt_destid_8_14 in struct IO_APIC_route_entry). Of course, the Extended Dest ID needs the support of the underlying hypervisor. The latest Hyper-V has added the support recently: with this commit, on such a Hyper-V host, Linux VM does not use hyperv-iommu.c because hyperv_prepare_irq_remapping() returns -ENODEV; instead, Linux kernel's generic support of Extended Dest ID from David is used, meaning that Linux VM is able to support up to 32K CPUs, and IOAPIC interrupts can be routed to all the CPUs. On an old Hyper-V host that doesn't support the Extended Dest ID, nothing changes with this commit: Linux VM is still able to bring up the CPUs with > 255 APIC IDs with the help of hyperv-iommu.c, but IOAPIC interrupts still can not go to such CPUs, and the kdump kernel still can not work properly on such CPUs. [ tglx: Updated comment as suggested by David ] Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: David Woodhouse <dwmw@amazon.co.uk> Link: https://lore.kernel.org/r/20201103011136.59108-1-decui@microsoft.com
2020-11-03Merge tag 'x86_seves_for_v5.10_rc3' of ↵Linus Torvalds4-7/+144
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 SEV-ES fixes from Borislav Petkov: "A couple of changes to the SEV-ES code to perform more stringent hypervisor checks before enabling encryption (Joerg Roedel)" * tag 'x86_seves_for_v5.10_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/sev-es: Do not support MMIO to/from encrypted memory x86/head/64: Check SEV encryption before switching to kernel page-table x86/boot/compressed/64: Check SEV encryption in 64-bit boot-path x86/boot/compressed/64: Sanity-check CPUID results in the early #VC handler x86/boot/compressed/64: Introduce sev_status
2020-11-02x86/mtrr: Fix a kernel-doc markupMauro Carvalho Chehab1-1/+2
Kernel-doc markup should use this format: identifier - description Fix it. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/2217cd4ae9e561da2825485eb97de77c65741489.1603469755.git.mchehab+huawei@kernel.org
2020-11-02x86/mce: Enable additional error logging on certain Intel CPUsTony Luck1-0/+20
The Xeon versions of Sandy Bridge, Ivy Bridge and Haswell support an optional additional error logging mode which is enabled by an MSR. Previously, this mode was enabled from the mcelog(8) tool via /dev/cpu, but userspace should not be poking at MSRs. So move the enabling into the kernel. [ bp: Correct the explanation why this is done. ] Suggested-by: Boris Petkov <bp@alien8.de> Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20201030190807.GA13884@agluck-desk2.amr.corp.intel.com
2020-10-29x86/build: Fix vmlinux size check on 64-bitArvind Sankar2-20/+12
Commit b4e0409a36f4 ("x86: check vmlinux limits, 64-bit") added a check that the size of the 64-bit kernel is less than KERNEL_IMAGE_SIZE. The check uses (_end - _text), but this is not enough. The initial PMD used in startup_64() (level2_kernel_pgt) can only map upto KERNEL_IMAGE_SIZE from __START_KERNEL_map, not from _text, and the modules area (MODULES_VADDR) starts at KERNEL_IMAGE_SIZE. The correct check is what is currently done for 32-bit, since LOAD_OFFSET is defined appropriately for the two architectures. Just check (_end - LOAD_OFFSET) against KERNEL_IMAGE_SIZE unconditionally. Note that on 32-bit, the limit is not strict: KERNEL_IMAGE_SIZE is not really used by the main kernel. The higher the kernel is located, the less the space available for the vmalloc area. However, it is used by KASLR in the compressed stub to limit the maximum address of the kernel to a safe value. Clean up various comments to clarify that despite the name, KERNEL_IMAGE_SIZE is not a limit on the size of the kernel image, but a limit on the maximum virtual address that the image can occupy. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20201029161903.2553528-1-nivedita@alum.mit.edu
2020-10-29x86/sev-es: Do not support MMIO to/from encrypted memoryJoerg Roedel1-7/+13
MMIO memory is usually not mapped encrypted, so there is no reason to support emulated MMIO when it is mapped encrypted. Prevent a possible hypervisor attack where a RAM page is mapped as an MMIO page in the nested page-table, so that any guest access to it will trigger a #VC exception and leak the data on that page to the hypervisor via the GHCB (like with valid MMIO). On the read side this attack would allow the HV to inject data into the guest. Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lkml.kernel.org/r/20201028164659.27002-6-joro@8bytes.org
2020-10-29x86/head/64: Check SEV encryption before switching to kernel page-tableJoerg Roedel1-0/+16
When SEV is enabled, the kernel requests the C-bit position again from the hypervisor to build its own page-table. Since the hypervisor is an untrusted source, the C-bit position needs to be verified before the kernel page-table is used. Call sev_verify_cbit() before writing the CR3. [ bp: Massage. ] Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lkml.kernel.org/r/20201028164659.27002-5-joro@8bytes.org
2020-10-29x86/boot/compressed/64: Check SEV encryption in 64-bit boot-pathJoerg Roedel1-0/+89
Check whether the hypervisor reported the correct C-bit when running as an SEV guest. Using a wrong C-bit position could be used to leak sensitive data from the guest to the hypervisor. The check function is in a separate file: arch/x86/kernel/sev_verify_cbit.S so that it can be re-used in the running kernel image. [ bp: Massage. ] Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lkml.kernel.org/r/20201028164659.27002-4-joro@8bytes.org
2020-10-29x86/boot/compressed/64: Sanity-check CPUID results in the early #VC handlerJoerg Roedel1-0/+26
The early #VC handler which doesn't have a GHCB can only handle CPUID exit codes. It is needed by the early boot code to handle #VC exceptions raised in verify_cpu() and to get the position of the C-bit. But the CPUID information comes from the hypervisor which is untrusted and might return results which trick the guest into the no-SEV boot path with no C-bit set in the page-tables. All data written to memory would then be unencrypted and could leak sensitive data to the hypervisor. Add sanity checks to the early #VC handler to make sure the hypervisor can not pretend that SEV is disabled. [ bp: Massage a bit. ] Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lkml.kernel.org/r/20201028164659.27002-3-joro@8bytes.org
2020-10-29entry: Add support for TIF_NOTIFY_SIGNALJens Axboe1-2/+2
Add TIF_NOTIFY_SIGNAL handling in the generic entry code, which if set, will return true if signal_pending() is used in a wait loop. That causes an exit of the loop so that notify_signal tracehooks can be run. If the wait loop is currently inside a system call, the system call is restarted once task_work has been processed. In preparation for only having arch_do_signal() handle syscall restarts if _TIF_SIGPENDING isn't set, rename it to arch_do_signal_or_restart(). Pass in a boolean that tells the architecture specific signal handler if it should attempt to get a signal, or just process a potential syscall restart. For !CONFIG_GENERIC_ENTRY archs, add the TIF_NOTIFY_SIGNAL handling to get_signal(). This is done to minimize the needed architecture changes to support this feature. Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Link: https://lore.kernel.org/r/20201026203230.386348-3-axboe@kernel.dk
2020-10-28x86/kvm: Enable 15-bit extension when KVM_FEATURE_MSI_EXT_DEST_ID detectedDavid Woodhouse1-0/+6
This allows the host to indicate that MSI emulation supports 15-bit destination IDs, allowing up to 32768 CPUs without interrupt remapping. cf. https://patchwork.kernel.org/patch/11816693/ for qemu Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Link: https://lore.kernel.org/r/20201024213535.443185-36-dwmw2@infradead.org
2020-10-28x86/apic: Support 15 bits of APIC ID in MSI where availableDavid Woodhouse2-2/+25
Some hypervisors can allow the guest to use the Extended Destination ID field in the MSI address to address up to 32768 CPUs. This applies to all downstream devices which generate MSI cycles, including HPET, I/O-APIC and PCI MSI. HPET and PCI MSI use the same __irq_msi_compose_msg() function, while I/O-APIC generates its own and had support for the extended bits added in a previous commit. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201024213535.443185-33-dwmw2@infradead.org
2020-10-28x86/ioapic: Handle Extended Destination ID field in RTEDavid Woodhouse1-5/+15
Bits 63-48 of the I/OAPIC Redirection Table Entry map directly to bits 19-4 of the address used in the resulting MSI cycle. Historically, the x86 MSI format only used the top 8 of those 16 bits as the destination APIC ID, and the "Extended Destination ID" in the lower 8 bits was unused. With interrupt remapping, the lowest bit of the Extended Destination ID (bit 48 of RTE, bit 4 of MSI address) is now used to indicate a remappable format MSI. A hypervisor can use the other 7 bits of the Extended Destination ID to permit guests to address up to 15 bits of APIC IDs, thus allowing 32768 vCPUs before having to expose a vIOMMU and interrupt remapping to the guest. No behavioural change in this patch, since nothing yet permits APIC IDs above 255 to be used with the non-IR I/OAPIC domain. [ tglx: Converted it to the cleaned up entry/msi_msg format and added commentry ] Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201024213535.443185-32-dwmw2@infradead.org
2020-10-28x86/ioapic: Use irq_find_matching_fwspec() to find remapping irqdomainDavid Woodhouse1-12/+13
All possible parent domains have a select method now. Make use of it. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201024213535.443185-29-dwmw2@infradead.org
2020-10-28x86/hpet: Use irq_find_matching_fwspec() to find remapping irqdomainDavid Woodhouse1-10/+14
All possible parent domains have a select method now. Make use of it. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201024213535.443185-28-dwmw2@infradead.org
2020-10-28x86/apic: Add select() method on vector irqdomainDavid Woodhouse1-0/+43
This will be used to select the irqdomain for I/O-APIC and HPET. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201024213535.443185-24-dwmw2@infradead.org
2020-10-28x86/ioapic: Generate RTE directly from parent irqchip's MSI messageDavid Woodhouse1-31/+72
The I/O-APIC generates an MSI cycle with address/data bits taken from its Redirection Table Entry in some combination which used to make sense, but now is just a bunch of bits which get passed through in some seemingly arbitrary order. Instead of making IRQ remapping drivers directly frob the I/OA-PIC RTE, let them just do their job and generate an MSI message. The bit swizzling to turn that MSI message into the I/O-APIC's RTE is the same in all cases, since it's a function of the I/O-APIC hardware. The IRQ remappers have no real need to get involved with that. The only slight caveat is that the I/OAPIC is interpreting some of those fields too, and it does want the 'vector' field to be unique to make EOI work. The AMD IOMMU happens to put its IRTE index in the bits that the I/O-APIC thinks are the vector field, and accommodates this requirement by reserving the first 32 indices for the I/O-APIC. The Intel IOMMU doesn't actually use the bits that the I/O-APIC thinks are the vector field, so it fills in the 'pin' value there instead. [ tglx: Replaced the unreadably macro maze with the cleaned up RTE/msi_msg bitfields and added commentry to explain the mapping magic ] Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201024213535.443185-22-dwmw2@infradead.org
2020-10-28x86/ioapic: Cleanup IO/APIC route entry structsThomas Gleixner1-79/+65
Having two seperate structs for the I/O-APIC RTE entries (non-remapped and DMAR remapped) requires type casts and makes it hard to map. Combine them in IO_APIC_routing_entry by defining a union of two 64bit bitfields. Use naming which reflects which bits are shared and which bits are actually different for the operating modes. [dwmw2: Fix it up and finish the job, pulling the 32-bit w1,w2 words for register access into the same union and eliminating a few more places where bits were accessed through masks and shifts.] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201024213535.443185-21-dwmw2@infradead.org
2020-10-28x86/io_apic: Cleanup trigger/polarity helpersThomas Gleixner1-129/+115
'trigger' and 'polarity' are used throughout the I/O-APIC code for handling the trigger type (edge/level) and the active low/high configuration. While there are defines for initializing these variables and struct members, they are not used consequently and the meaning of 'trigger' and 'polarity' is opaque and confusing at best. Rename them to 'is_level' and 'active_low' and make them boolean in various structs so it's entirely clear what the meaning is. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201024213535.443185-20-dwmw2@infradead.org
2020-10-28x86/msi: Provide msi message shadow structsThomas Gleixner1-16/+19
Create shadow structs with named bitfields for msi_msg data, address_lo and address_hi and use them in the MSI message composer. Provide a function to retrieve the destination ID. This could be inline, but that'd create a circular header dependency. [dwmw2: fix bitfields not all to be a union] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201024213535.443185-13-dwmw2@infradead.org
2020-10-28x86/hpet: Move MSI support into hpet.cDavid Woodhouse2-117/+112
This isn't really dependent on PCI MSI; it's just generic MSI which is now supported by the generic x86_vector_domain. Move the HPET MSI support back into hpet.c with the rest of the HPET support. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201024213535.443185-11-dwmw2@infradead.org
2020-10-28x86/apic: Always provide irq_compose_msi_msg() method for vector domainDavid Woodhouse3-37/+38
This shouldn't be dependent on PCI_MSI. HPET and I/O-APIC can deliver interrupts through MSI without having any PCI in the system at all. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201024213535.443185-10-dwmw2@infradead.org
2020-10-28x86/apic: Cleanup destination modeThomas Gleixner12-24/+17
apic::irq_dest_mode is actually a boolean, but defined as u32 and named in a way which does not explain what it means. Make it a boolean and rename it to 'dest_mode_logical' Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201024213535.443185-9-dwmw2@infradead.org
2020-10-28x86/apic: Get rid of apic:: Dest_logicalThomas Gleixner10-33/+14
struct apic has two members which store information about the destination mode: dest_logical and irq_dest_mode. dest_logical contains a mask which was historically used to set the destination mode in IPI messages. Over time the usage was reduced and the logical/physical functions were seperated. There are only a few places which still use 'dest_logical' but they can use 'irq_dest_mode' instead. irq_dest_mode is actually a boolean where 0 means physical destination mode and 1 means logical destination mode. Of course the name does not reflect the functionality. This will be cleaned up in a subsequent change. Remove apic::dest_logical and fixup the remaining users. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201024213535.443185-8-dwmw2@infradead.org
2020-10-28x86/apic: Replace pointless apic:: Dest_logical usageThomas Gleixner3-5/+5
All these functions are only used for logical destination mode. So reading the destination mode mask from the apic structure is a pointless exercise. Just hand in the proper constant: APIC_DEST_LOGICAL. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201024213535.443185-7-dwmw2@infradead.org
2020-10-28x86/apic: Cleanup delivery mode definesThomas Gleixner9-17/+18
The enum ioapic_irq_destination_types and the enumerated constants starting with 'dest_' are gross misnomers because they describe the delivery mode. Rename then enum and the constants so they actually make sense. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201024213535.443185-6-dwmw2@infradead.org
2020-10-28x86/devicetree: Fix the ioapic interrupt type tableThomas Gleixner1-15/+15
The ioapic interrupt type table is wrong as it assumes that polarity in IO/APIC context means active high when set. But the IO/APIC polarity is working the other way round. This works because the ordering of the entries is consistent with the device tree and the type information is not used by the IO/APIC interrupt chip. The whole trigger and polarity business of IO/APIC is misleading and the corresponding constants which are defined as 0/1 are not used consistently and are going to be removed. Rename the type table members to 'is_level' and 'active_low' and adjust the type information for consistency sake. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201024213535.443185-5-dwmw2@infradead.org
2020-10-28x86/apic/uv: Fix inconsistent destination modeThomas Gleixner1-1/+1
The UV x2apic is strictly using physical destination mode, but apic::dest_logical is initialized with APIC_DEST_LOGICAL. This does not matter much because UV does not use any of the generic functions which use apic::dest_logical, but is still inconsistent. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201024213535.443185-4-dwmw2@infradead.org
2020-10-28x86/msi: Only use high bits of MSI address for DMAR unitDavid Woodhouse1-6/+27
The Intel IOMMU has an MSI-like configuration for its interrupt, but it isn't really MSI. So it gets to abuse the high 32 bits of the address, and puts the high 24 bits of the extended APIC ID there. This isn't something that can be used in the general case for real MSIs, since external devices using the high bits of the address would be performing writes to actual memory space above 4GiB, not targeted at the APIC. Factor the hack out and allow it only to be used when appropriate, adding a WARN_ON_ONCE() if other MSIs are targeted at an unreachable APIC ID. That should never happen since the compatibility MSI messages are not used when Interrupt Remapping is enabled. The x2apic_enabled() check isn't needed because Linux won't bring up CPUs with higher APIC IDs unless IR and x2apic are enabled anyway. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201024213535.443185-3-dwmw2@infradead.org
2020-10-28x86/apic: Fix x2apic enablement without interrupt remappingDavid Woodhouse2-6/+17
Currently, Linux as a hypervisor guest will enable x2apic only if there are no CPUs present at boot time with an APIC ID above 255. Hotplugging a CPU later with a higher APIC ID would result in a CPU which cannot be targeted by external interrupts. Add a filter in x2apic_apic_id_valid() which can be used to prevent such CPUs from coming online, and allow x2apic to be enabled even if they are present at boot time. Fixes: ce69a784504 ("x86/apic: Enable x2APIC without interrupt remapping under KVM") Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201024213535.443185-2-dwmw2@infradead.org
2020-10-28x86/setup: Remove unused MCA variablesBorislav Petkov1-5/+0
Commit bb8187d35f82 ("MCA: delete all remaining traces of microchannel bus support.") removed the remaining traces of Micro Channel Architecture support but one trace remained - three variables in setup.c which have been unused since 2012 at least. Drop them finally. Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20201021165614.23023-1-bp@alien8.de
2020-10-28x86/debug: Fix DR_STEP vs ptrace_get_debugreg(6)Peter Zijlstra1-3/+6
Commit d53d9bc0cf78 ("x86/debug: Change thread.debugreg6 to thread.virtual_dr6") changed the semantics of the variable from random collection of bits, to exactly only those bits that ptrace() needs. Unfortunately this lost DR_STEP for PTRACE_{BLOCK,SINGLE}STEP. Furthermore, it turns out that userspace expects DR_STEP to be unconditionally available, even for manual TF usage outside of PTRACE_{BLOCK,SINGLE}_STEP. Fixes: d53d9bc0cf78 ("x86/debug: Change thread.debugreg6 to thread.virtual_dr6") Reported-by: Kyle Huey <me@kylehuey.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Kyle Huey <me@kylehuey.com> Link: https://lore.kernel.org/r/20201027183330.GM2628@hirez.programming.kicks-ass.net
2020-10-28x86/debug: Only clear/set ->virtual_dr6 for userspace #DBPeter Zijlstra1-6/+6
The ->virtual_dr6 is the value used by ptrace_{get,set}_debugreg(6). A kernel #DB clearing it could mean spurious malfunction of ptrace() expectations. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Kyle Huey <me@kylehuey.com> Link: https://lore.kernel.org/r/20201027093608.028952500@infradead.org
2020-10-28x86/debug: Fix BTF handlingPeter Zijlstra1-7/+21
The SDM states that #DB clears DEBUGCTLMSR_BTF, this means that when the bit is set for userspace (TIF_BLOCKSTEP) and a kernel #DB happens first, the BTF bit meant for userspace execution is lost. Have the kernel #DB handler restore the BTF bit when it was requested for userspace. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Kyle Huey <me@kylehuey.com> Link: https://lore.kernel.org/r/20201027093607.956147736@infradead.org
2020-10-28Merge tag 'x86-urgent-2020-10-27' of ↵Linus Torvalds3-10/+11
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "A couple of x86 fixes which missed rc1 due to my stupidity: - Drop lazy TLB mode before switching to the temporary address space for text patching. text_poke() switches to the temporary mm which clears the lazy mode and restores the original mm afterwards. Due to clearing lazy mode this might restore a already dead mm if exit_mmap() runs in parallel on another CPU. - Document the x32 syscall design fail vs. syscall numbers 512-547 properly. - Fix the ORC unwinder to handle the inactive task frame correctly. This was unearthed due to the slightly different code generation of gcc-10. - Use an up to date screen_info for the boot params of kexec instead of the possibly stale and invalid version which happened to be valid when the kexec kernel was loaded" * tag 'x86-urgent-2020-10-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/alternative: Don't call text_poke() in lazy TLB mode x86/syscalls: Document the fact that syscalls 512-547 are a legacy mistake x86/unwind/orc: Fix inactive tasks with stack pointer in %sp on GCC 10 compiled kernels hyperv_fb: Update screen_info after removing old framebuffer x86/kexec: Use up-to-dated screen_info copy to fill boot params
2020-10-27x86/resctrl: Correct MBM total and local valuesFenghua Yu3-2/+85
Intel Memory Bandwidth Monitoring (MBM) counters may report system memory bandwidth incorrectly on some Intel processors. The errata SKX99 for Skylake server, BDF102 for Broadwell server, and the correction factor table are documented in Documentation/x86/resctrl.rst. Intel MBM counters track metrics according to the assigned Resource Monitor ID (RMID) for that logical core. The IA32_QM_CTR register (MSR 0xC8E) used to report these metrics, may report incorrect system bandwidth for certain RMID values. Due to the errata, system memory bandwidth may not match what is reported. To work around the errata, correct MBM total and local readings using a correction factor table. If rmid > rmid threshold, MBM total and local values should be multiplied by the correction factor. [ bp: Mark mbm_cf_table[] __initdata. ] Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Link: https://lkml.kernel.org/r/20201014004927.1839452-3-fenghua.yu@intel.com
2020-10-26x86: Reclaim TIF_IA32 and TIF_X32Gabriel Krisman Bertazi1-6/+0
Now that these flags are no longer used, reclaim those TIF bits. Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201004032536.1229030-11-krisman@collabora.com