aboutsummaryrefslogtreecommitdiff
path: root/arch/x86/kernel/cpu
AgeCommit message (Collapse)AuthorFilesLines
2020-03-21Merge branch 'x86/kdump' into locking/kcsan, to resolve conflictsIngo Molnar26-351/+446
Conflicts: arch/x86/purgatory/Makefile Signed-off-by: Ingo Molnar <[email protected]>
2020-03-15Merge tag 'ras-urgent-2020-03-15' of ↵Linus Torvalds2-6/+12
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RAS fixes from Thomas Gleixner: "Two RAS related fixes: - Shut down the per CPU thermal throttling poll work properly when a CPU goes offline. The missing shutdown caused the poll work to be migrated to a unbound worker which triggered warnings about the usage of smp_processor_id() in preemptible context - Fix the PPIN feature initialization which missed to enable the functionality when PPIN_CTL was enabled but the MSR locked against updates" * tag 'ras-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mce: Fix logic and comments around MSR_PPIN_CTL x86/mce/therm_throt: Undo thermal polling properly on CPU offline
2020-03-12x86/cpu/amd: Call init_amd_zn() om Family 19h processors tooKim Phillips1-1/+2
Family 19h CPUs are Zen-based and still share most architectural features with Family 17h CPUs, and therefore still need to call init_amd_zn() e.g., to set the RECLAIM_DISTANCE override. init_amd_zn() also sets X86_FEATURE_ZEN, which today is only used in amd_set_core_ssb_state(), which isn't called on some late model Family 17h CPUs, nor on any Family 19h CPUs: X86_FEATURE_AMD_SSBD replaces X86_FEATURE_LS_CFG_SSBD on those later model CPUs, where the SSBD mitigation is done via the SPEC_CTRL MSR instead of the LS_CFG MSR. Family 19h CPUs also don't have the erratum where the CPB feature bit isn't set, but that code can stay unchanged and run safely on Family 19h. Signed-off-by: Kim Phillips <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-03-10x86/mce/dev-mcelog: Dynamically allocate space for machine check recordsTony Luck1-20/+27
We have had a hard coded limit of 32 machine check records since the dawn of time. But as numbers of cores increase, it is possible for more than 32 errors to be reported before a user process reads from /dev/mcelog. In this case the additional errors are lost. Keep 32 as the minimum. But tune the maximum value up based on the number of processors. Signed-off-by: Tony Luck <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-02-27x86/mce: Fix logic and comments around MSR_PPIN_CTLTony Luck1-4/+5
There are two implemented bits in the PPIN_CTL MSR: Bit 0: LockOut (R/WO) Set 1 to prevent further writes to MSR_PPIN_CTL. Bit 1: Enable_PPIN (R/W) If 1, enables MSR_PPIN to be accessible using RDMSR. If 0, an attempt to read MSR_PPIN will cause #GP. So there are four defined values: 0: PPIN is disabled, PPIN_CTL may be updated 1: PPIN is disabled. PPIN_CTL is locked against updates 2: PPIN is enabled. PPIN_CTL may be updated 3: PPIN is enabled. PPIN_CTL is locked against updates Code would only enable the X86_FEATURE_INTEL_PPIN feature for case "2". When it should have done so for both case "2" and case "3". Fix the final test to just check for the enable bit. Also fix some of the other comments in this function. Fixes: 3f5a7896a509 ("x86/mce: Include the PPIN in MCE records when available") Signed-off-by: Tony Luck <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Cc: <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-02-27x86/pkeys: Manually set X86_FEATURE_OSPKE to preserve existing changesSean Christopherson1-1/+1
Explicitly set X86_FEATURE_OSPKE via set_cpu_cap() instead of calling get_cpu_cap() to pull the feature bit from CPUID after enabling CR4.PKE. Invoking get_cpu_cap() effectively wipes out any {set,clear}_cpu_cap() changes that were made between this_cpu->c_init() and setup_pku(), as all non-synthetic feature words are reinitialized from the CPU's CPUID values. Blasting away capability updates manifests most visibility when running on a VMX capable CPU, but with VMX disabled by BIOS. To indicate that VMX is disabled, init_ia32_feat_ctl() clears X86_FEATURE_VMX, using clear_cpu_cap() instead of setup_clear_cpu_cap() so that KVM can report which CPU is misconfigured (KVM needs to probe every CPU anyways). Restoring X86_FEATURE_VMX from CPUID causes KVM to think VMX is enabled, ultimately leading to an unexpected #GP when KVM attempts to do VMXON. Arguably, init_ia32_feat_ctl() should use setup_clear_cpu_cap() and let KVM figure out a different way to report the misconfigured CPU, but VMX is not the only feature bit that is affected, i.e. there is precedent that tweaking feature bits via {set,clear}_cpu_cap() after ->c_init() is expected to work. Most notably, x86_init_rdrand()'s clearing of X86_FEATURE_RDRAND when RDRAND malfunctions is also overwritten. Fixes: 0697694564c8 ("x86/mm/pkeys: Actually enable Memory Protection Keys in the CPU") Reported-by: Jacob Keller <[email protected]> Signed-off-by: Sean Christopherson <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Acked-by: Dave Hansen <[email protected]> Tested-by: Jacob Keller <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected]
2020-02-27x86/entry/32: Force MCE through do_mce()Thomas Gleixner1-0/+3
Remove the pointless difference between 32 and 64 bit to make further unifications simpler. Signed-off-by: Thomas Gleixner <[email protected]> Reviewed-by: Frederic Weisbecker <[email protected]> Reviewed-by: Alexandre Chartre <[email protected]> Reviewed-by: Andy Lutomirski <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-02-27x86/mce: Disable tracing and kprobes on do_machine_check()Andy Lutomirski1-2/+10
do_machine_check() can be raised in almost any context including the most fragile ones. Prevent kprobes and tracing. Signed-off-by: Andy Lutomirski <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Reviewed-by: Borislav Petkov <[email protected]> Reviewed-by: Alexandre Chartre <[email protected]> Reviewed-by: Andy Lutomirski <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-02-25x86/mce/therm_throt: Undo thermal polling properly on CPU offlineThomas Gleixner1-2/+7
Chris Wilson reported splats from running the thermal throttling workqueue callback on offlined CPUs. The problem is that that callback should not even run on offlined CPUs but it happens nevertheless because the offlining callback thermal_throttle_offline() does not symmetrically undo the setup work done in its onlining counterpart. IOW, 1. The thermal interrupt vector should be masked out before ... 2. ... cancelling any pending work synchronously so that no new work is enqueued anymore. Do those things and fix the issue properly. [ bp: Write commit message. ] Fixes: f6656208f04e ("x86/mce/therm_throt: Optimize notifications of thermal throttle") Reported-by: Chris Wilson <[email protected]> Tested-by: Pandruvada, Srinivas <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Link: https://lkml.kernel.org/r/158120068234.18291.7938335950259651295@skylake-alporthouse-com
2020-02-22Merge tag 'ras-urgent-2020-02-22' of ↵Linus Torvalds1-23/+27
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RAS fixes from Thomas Gleixner: "Two fixes for the AMD MCE driver: - Populate the per CPU MCA bank descriptor pointer only after it has been completely set up to prevent a use-after-free in case that one of the subsequent initialization step fails - Implement a proper release function for the sysfs entries of MCA threshold controls instead of freeing the memory right in the CPU teardown code, which leads to another use-after-free when the associated sysfs file is opened and accessed" * tag 'ras-urgent-2020-02-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mce/amd: Fix kobject lifetime x86/mce/amd: Publish the bank pointer only after setup has succeeded
2020-02-20x86/split_lock: Enable split lock detection by kernelPeter Zijlstra (Intel)2-0/+177
A split-lock occurs when an atomic instruction operates on data that spans two cache lines. In order to maintain atomicity the core takes a global bus lock. This is typically >1000 cycles slower than an atomic operation within a cache line. It also disrupts performance on other cores (which must wait for the bus lock to be released before their memory operations can complete). For real-time systems this may mean missing deadlines. For other systems it may just be very annoying. Some CPUs have the capability to raise an #AC trap when a split lock is attempted. Provide a command line option to give the user choices on how to handle this: split_lock_detect= off - not enabled (no traps for split locks) warn - warn once when an application does a split lock, but allow it to continue running. fatal - Send SIGBUS to applications that cause split lock On systems that support split lock detection the default is "warn". Note that if the kernel hits a split lock in any mode other than "off" it will OOPs. One implementation wrinkle is that the MSR to control the split lock detection is per-core, not per thread. This might result in some short lived races on HT systems in "warn" mode if Linux tries to enable on one thread while disabling on the other. Race analysis by Sean Christopherson: - Toggling of split-lock is only done in "warn" mode. Worst case scenario of a race is that a misbehaving task will generate multiple #AC exceptions on the same instruction. And this race will only occur if both siblings are running tasks that generate split-lock #ACs, e.g. a race where sibling threads are writing different values will only occur if CPUx is disabling split-lock after an #AC and CPUy is re-enabling split-lock after *its* previous task generated an #AC. - Transitioning between off/warn/fatal modes at runtime isn't supported and disabling is tracked per task, so hardware will always reach a steady state that matches the configured mode. I.e. split-lock is guaranteed to be enabled in hardware once all _TIF_SLD threads have been scheduled out. Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Co-developed-by: Fenghua Yu <[email protected]> Signed-off-by: Fenghua Yu <[email protected]> Co-developed-by: Tony Luck <[email protected]> Signed-off-by: Tony Luck <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-02-19x86/cpu/amd: Enable the fixed Instructions Retired counter IRPERFKim Phillips1-0/+14
Commit aaf248848db50 ("perf/x86/msr: Add AMD IRPERF (Instructions Retired) performance counter") added support for access to the free-running counter via 'perf -e msr/irperf/', but when exercised, it always returns a 0 count: BEFORE: $ perf stat -e instructions,msr/irperf/ true Performance counter stats for 'true': 624,833 instructions 0 msr/irperf/ Simply set its enable bit - HWCR bit 30 - to make it start counting. Enablement is restricted to all machines advertising IRPERF capability, except those susceptible to an erratum that makes the IRPERF return bad values. That erratum occurs in Family 17h models 00-1fh [1], but not in F17h models 20h and above [2]. AFTER (on a family 17h model 31h machine): $ perf stat -e instructions,msr/irperf/ true Performance counter stats for 'true': 621,690 instructions 622,490 msr/irperf/ [1] Revision Guide for AMD Family 17h Models 00h-0Fh Processors [2] Revision Guide for AMD Family 17h Models 30h-3Fh Processors The revision guides are available from the bugzilla Link below. [ bp: Massage commit message. ] Fixes: aaf248848db50 ("perf/x86/msr: Add AMD IRPERF (Instructions Retired) performance counter") Signed-off-by: Kim Phillips <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: [email protected] Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537 Link: http://lkml.kernel.org/r/[email protected]
2020-02-19x86/mce: Do not log spurious corrected mce errorsPrarit Bhargava3-0/+21
A user has reported that they are seeing spurious corrected errors on their hardware. Intel Errata HSD131, HSM142, HSW131, and BDM48 report that "spurious corrected errors may be logged in the IA32_MC0_STATUS register with the valid field (bit 63) set, the uncorrected error field (bit 61) not set, a Model Specific Error Code (bits [31:16]) of 0x000F, and an MCA Error Code (bits [15:0]) of 0x0005." The Errata PDFs are linked in the bugzilla below. Block these spurious errors from the console and logs. [ bp: Move the intel_filter_mce() header declarations into the already existing CONFIG_X86_MCE_INTEL ifdeffery. ] Co-developed-by: Alexander Krupp <[email protected]> Signed-off-by: Alexander Krupp <[email protected]> Signed-off-by: Prarit Bhargava <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Link: https://bugzilla.kernel.org/show_bug.cgi?id=206587 Link: https://lkml.kernel.org/r/[email protected]
2020-02-17x86/cpu: Move prototype for get_umwait_control_msr() to a global locationBenjamin Thiel1-0/+1
.. in order to fix a -Wmissing-prototypes warning. No functional change. Signed-off-by: Benjamin Thiel <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected]
2020-02-14x86/mce/amd: Fix kobject lifetimeThomas Gleixner1-6/+11
Accessing the MCA thresholding controls in sysfs concurrently with CPU hotplug can lead to a couple of KASAN-reported issues: BUG: KASAN: use-after-free in sysfs_file_ops+0x155/0x180 Read of size 8 at addr ffff888367578940 by task grep/4019 and BUG: KASAN: use-after-free in show_error_count+0x15c/0x180 Read of size 2 at addr ffff888368a05514 by task grep/4454 for example. Both result from the fact that the threshold block creation/teardown code frees the descriptor memory itself instead of defining proper ->release function and leaving it to the driver core to take care of that, after all sysfs accesses have completed. Do that and get rid of the custom freeing code, fixing the above UAFs in the process. [ bp: write commit message. ] Fixes: 95268664390b ("[PATCH] x86_64: mce_amd support for family 0x10 processors") Signed-off-by: Thomas Gleixner <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Cc: <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-02-13x86/mce/amd: Publish the bank pointer only after setup has succeededBorislav Petkov1-17/+16
threshold_create_bank() creates a bank descriptor per MCA error thresholding counter which can be controlled over sysfs. It publishes the pointer to that bank in a per-CPU variable and then goes on to create additional thresholding blocks if the bank has such. However, that creation of additional blocks in allocate_threshold_blocks() can fail, leading to a use-after-free through the per-CPU pointer. Therefore, publish that pointer only after all blocks have been setup successfully. Fixes: 019f34fccfd5 ("x86, MCE, AMD: Move shared bank to node descriptor") Reported-by: Saar Amar <[email protected]> Reported-by: Dan Carpenter <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Cc: <[email protected]> Link: http://lkml.kernel.org/r/[email protected]
2020-02-08Merge branch 'merge.nfs-fs_parse.1' of ↵Linus Torvalds1-8/+3
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs file system parameter updates from Al Viro: "Saner fs_parser.c guts and data structures. The system-wide registry of syntax types (string/enum/int32/oct32/.../etc.) is gone and so is the horror switch() in fs_parse() that would have to grow another case every time something got added to that system-wide registry. New syntax types can be added by filesystems easily now, and their namespace is that of functions - not of system-wide enum members. IOW, they can be shared or kept private and if some turn out to be widely useful, we can make them common library helpers, etc., without having to do anything whatsoever to fs_parse() itself. And we already get that kind of requests - the thing that finally pushed me into doing that was "oh, and let's add one for timeouts - things like 15s or 2h". If some filesystem really wants that, let them do it. Without somebody having to play gatekeeper for the variants blessed by direct support in fs_parse(), TYVM. Quite a bit of boilerplate is gone. And IMO the data structures make a lot more sense now. -200LoC, while we are at it" * 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (25 commits) tmpfs: switch to use of invalfc() cgroup1: switch to use of errorfc() et.al. procfs: switch to use of invalfc() hugetlbfs: switch to use of invalfc() cramfs: switch to use of errofc() et.al. gfs2: switch to use of errorfc() et.al. fuse: switch to use errorfc() et.al. ceph: use errorfc() and friends instead of spelling the prefix out prefix-handling analogues of errorf() and friends turn fs_param_is_... into functions fs_parse: handle optional arguments sanely fs_parse: fold fs_parameter_desc/fs_parameter_spec fs_parser: remove fs_parameter_description name field add prefix to fs_context->log ceph_parse_param(), ceph_parse_mon_ips(): switch to passing fc_log new primitive: __fs_parse() switch rbd and libceph to p_log-based primitives struct p_log, variants of warnf() et.al. taking that one instead teach logfc() to handle prefices, give it saner calling conventions get rid of cg_invalf() ...
2020-02-07fs_parse: fold fs_parameter_desc/fs_parameter_specAl Viro1-7/+3
The former contains nothing but a pointer to an array of the latter... Signed-off-by: Al Viro <[email protected]>
2020-02-07fs_parser: remove fs_parameter_description name fieldEric Sandeen1-1/+0
Unused now. Signed-off-by: Eric Sandeen <[email protected]> Acked-by: David Howells <[email protected]> Signed-off-by: Al Viro <[email protected]>
2020-02-04proc: convert everything to "struct proc_ops"Alexey Dobriyan1-10/+11
The most notable change is DEFINE_SHOW_ATTRIBUTE macro split in seq_file.h. Conversion rule is: llseek => proc_lseek unlocked_ioctl => proc_ioctl xxx => proc_xxx delete ".owner = THIS_MODULE" line [[email protected]: fix drivers/isdn/capi/kcapi_proc.c] [[email protected]: fix kernel/sched/psi.c] Link: http://lkml.kernel.org/r/[email protected] Link: http://lkml.kernel.org/r/20191225172546.GB13378@avx2 Signed-off-by: Alexey Dobriyan <[email protected]> Signed-off-by: Stephen Rothwell <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2020-01-31Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds1-23/+25
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "Misc fixes: - three fixes and a cleanup for the resctrl code - a HyperV fix - a fix to /proc/kcore contents in live debugging sessions - a fix for the x86 decoder opcode map" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/decoder: Add TEST opcode to Group3-2 x86/resctrl: Clean up unused function parameter in mkdir path x86/resctrl: Fix a deadlock due to inaccurate reference x86/resctrl: Fix use-after-free due to inaccurate refcount of rdtgroup x86/resctrl: Fix use-after-free when deleting resource groups x86/hyper-v: Add "polling" bit to hv_synic_sint x86/crash: Define arch_crash_save_vmcoreinfo() if CONFIG_CRASH_CORE=y
2020-01-30Merge tag 'mpx-for-linus' of ↵Linus Torvalds2-54/+0
git://git.kernel.org/pub/scm/linux/kernel/git/daveh/x86-mpx Pull x86 MPX removal from Dave Hansen: "MPX requires recompiling applications, which requires compiler support. Unfortunately, GCC 9.1 is expected to be be released without support for MPX. This means that there was only a relatively small window where folks could have ever used MPX. It failed to gain wide adoption in the industry, and Linux was the only mainstream OS to ever support it widely. Support for the feature may also disappear on future processors. This set completes the process that we started during the 5.4 merge window when the MPX prctl()s were removed. XSAVE support is left in place, which allows MPX-using KVM guests to continue to function" * tag 'mpx-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/daveh/x86-mpx: x86/mpx: remove MPX from arch/x86 mm: remove arch_bprm_mm_init() hook x86/mpx: remove bounds exception code x86/mpx: remove build infrastructure x86/alternatives: add missing insn.h include
2020-01-28Merge branch 'x86-mtrr-for-linus' of ↵Linus Torvalds1-41/+22
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 mtrr updates from Ingo Molnar: "Two changes: restrict /proc/mtrr to CAP_SYS_ADMIN, plus a cleanup" * 'x86-mtrr-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mtrr: Require CAP_SYS_ADMIN for all access x86/mtrr: Get rid of mtrr_seq_show() forward declaration
2020-01-28Merge branch 'x86-cpu-for-linus' of ↵Linus Torvalds12-134/+204
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cpu-features updates from Ingo Molnar: "The biggest change in this cycle was a large series from Sean Christopherson to clean up the handling of VMX features. This both fixes bugs/inconsistencies and makes the code more coherent and future-proof. There are also two cleanups and a minor TSX syslog messages enhancement" * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits) x86/cpu: Remove redundant cpu_detect_cache_sizes() call x86/cpu: Print "VMX disabled" error message iff KVM is enabled KVM: VMX: Allow KVM_INTEL when building for Centaur and/or Zhaoxin CPUs perf/x86: Provide stubs of KVM helpers for non-Intel CPUs KVM: VMX: Use VMX_FEATURE_* flags to define VMCS control bits KVM: VMX: Check for full VMX support when verifying CPU compatibility KVM: VMX: Use VMX feature flag to query BIOS enabling KVM: VMX: Drop initialization of IA32_FEAT_CTL MSR x86/cpufeatures: Add flag to track whether MSR IA32_FEAT_CTL is configured x86/cpu: Set synthetic VMX cpufeatures during init_ia32_feat_ctl() x86/cpu: Print VMX flags in /proc/cpuinfo using VMX_FEATURES_* x86/cpu: Detect VMX features on Intel, Centaur and Zhaoxin CPUs x86/vmx: Introduce VMX_FEATURES_* x86/cpu: Clear VMX feature flag if VMX is not fully enabled x86/zhaoxin: Use common IA32_FEAT_CTL MSR initialization x86/centaur: Use common IA32_FEAT_CTL MSR initialization x86/mce: WARN once if IA32_FEAT_CTL MSR is left unlocked x86/intel: Initialize IA32_FEAT_CTL MSR at boot tools/x86: Sync msr-index.h from kernel sources selftests, kvm: Replace manual MSR defs with common msr-index.h ...
2020-01-28Merge branch 'x86-cleanups-for-linus' of ↵Linus Torvalds2-8/+3
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cleanups from Ingo Molnar: "Misc cleanups all around the map" * 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/CPU/AMD: Remove amd_get_topology_early() x86/tsc: Remove redundant assignment x86/crash: Use resource_size() x86/cpu: Add a missing prototype for arch_smt_update() x86/nospec: Remove unused RSB_FILL_LOOPS x86/vdso: Provide missing include file x86/Kconfig: Correct spelling and punctuation Documentation/x86/boot: Fix typo x86/boot: Fix a comment's incorrect file reference x86/process: Remove set but not used variables prev and next x86/Kconfig: Fix Kconfig indentation
2020-01-28Merge branch 'x86-cache-for-linus' of ↵Linus Torvalds3-2/+93
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 resource control updates from Ingo Molnar: "The main change in this tree is the extension of the resctrl procfs ABI with a new file that helps tooling to navigate from tasks back to resctrl groups: /proc/{pid}/cpu_resctrl_groups. Also fix static key usage for certain feature combinations and simplify the task exit resctrl case" * 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/resctrl: Add task resctrl information display x86/resctrl: Check monitoring static key in the MBM overflow handler x86/resctrl: Do not reconfigure exiting tasks
2020-01-28Merge branch 'efi-core-for-linus' of ↵Linus Torvalds5-5/+5
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull EFI updates from Ingo Molnar: "The main changes in this cycle were: - Cleanup of the GOP [graphics output] handling code in the EFI stub - Complete refactoring of the mixed mode handling in the x86 EFI stub - Overhaul of the x86 EFI boot/runtime code - Increase robustness for mixed mode code - Add the ability to disable DMA at the root port level in the EFI stub - Get rid of RWX mappings in the EFI memory map and page tables, where possible - Move the support code for the old EFI memory mapping style into its only user, the SGI UV1+ support code. - plus misc fixes, updates, smaller cleanups. ... and due to interactions with the RWX changes, another round of PAT cleanups make a guest appearance via the EFI tree - with no side effects intended" * 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (75 commits) efi/x86: Disable instrumentation in the EFI runtime handling code efi/libstub/x86: Fix EFI server boot failure efi/x86: Disallow efi=old_map in mixed mode x86/boot/compressed: Relax sed symbol type regex for LLVM ld.lld efi/x86: avoid KASAN false positives when accessing the 1: 1 mapping efi: Fix handling of multiple efi_fake_mem= entries efi: Fix efi_memmap_alloc() leaks efi: Add tracking for dynamically allocated memmaps efi: Add a flags parameter to efi_memory_map efi: Fix comment for efi_mem_type() wrt absent physical addresses efi/arm: Defer probe of PCIe backed efifb on DT systems efi/x86: Limit EFI old memory map to SGI UV machines efi/x86: Avoid RWX mappings for all of DRAM efi/x86: Don't map the entire kernel text RW for mixed mode x86/mm: Fix NX bit clearing issue in kernel_map_pages_in_pgd efi/libstub/x86: Fix unused-variable warning efi/libstub/x86: Use mandatory 16-byte stack alignment in mixed mode efi/libstub/x86: Use const attribute for efi_is_64bit() efi: Allow disabling PCI busmastering on bridges during boot efi/x86: Allow translating 64-bit arguments for mixed mode calls ...
2020-01-27Merge tag 'x86-pti-2020-01-28' of ↵Linus Torvalds2-7/+15
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 pti updates from Thomas Gleixner: "The performance deterioration departement provides a few non-scary fixes and improvements: - Update the cached HLE state when the TSX state is changed via the new control register. This ensures feature bit consistency. - Exclude the new Zhaoxin CPUs from Spectre V2 and SWAPGS vulnerabilities" * tag 'x86-pti-2020-01-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/speculation/swapgs: Exclude Zhaoxin CPUs from SWAPGS vulnerability x86/speculation/spectre_v2: Exclude Zhaoxin CPUs from SPECTRE_V2 x86/cpu: Update cached HLE state on write to TSX_CTRL_CPUID_CLEAR
2020-01-27Merge branch 'ras-core-for-linus' of ↵Linus Torvalds5-45/+33
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RAS updates from Borislav Petkov: - Misc fixes to the MCE code all over the place, by Jan H. Schönherr. - Initial support for AMD F19h and other cleanups to amd64_edac, by Yazen Ghannam. - Other small cleanups. * 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: EDAC/mce_amd: Make fam_ops static global EDAC/amd64: Drop some family checks for newer systems EDAC/amd64: Add family ops for Family 19h Models 00h-0Fh x86/amd_nb: Add Family 19h PCI IDs EDAC/mce_amd: Always load on SMCA systems x86/MCE/AMD, EDAC/mce_amd: Add new Load Store unit McaType x86/mce: Fix use of uninitialized MCE message string x86/mce: Fix mce=nobootlog x86/mce: Take action on UCNA/Deferred errors again x86/mce: Remove mce_inject_log() in favor of mce_log() x86/mce: Pass MCE message to mce_panic() on failed kernel recovery x86/mce/therm_throt: Mark throttle_active_work() as __maybe_unused
2020-01-25x86/CPU/AMD: Remove amd_get_topology_early()Borislav Petkov1-8/+2
... and fold its function body into its single call site. No functional changes: # arch/x86/kernel/cpu/amd.o: text data bss dec hex filename 5994 385 1 6380 18ec amd.o.before 5994 385 1 6380 18ec amd.o.after md5: 99ec6daa095b502297884e949c520f90 amd.o.before.asm 99ec6daa095b502297884e949c520f90 amd.o.after.asm Signed-off-by: Borislav Petkov <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-01-23x86/mpx: remove MPX from arch/x86Dave Hansen2-54/+0
From: Dave Hansen <[email protected]> MPX is being removed from the kernel due to a lack of support in the toolchain going forward (gcc). This removes all the remaining (dead at this point) MPX handling code remaining in the tree. The only remaining code is the XSAVE support for MPX state which is currently needd for KVM to handle VMs which might use MPX. Cc: Peter Zijlstra (Intel) <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: [email protected] Cc: Linus Torvalds <[email protected]> Cc: Andrew Morton <[email protected]> Signed-off-by: Dave Hansen <[email protected]>
2020-01-20x86/resctrl: Clean up unused function parameter in mkdir pathXiaochen Shen1-11/+5
Commit 334b0f4e9b1b ("x86/resctrl: Fix a deadlock due to inaccurate reference") changed the argument to rdtgroup_kn_lock_live()/rdtgroup_kn_unlock() within mkdir_rdt_prepare(). That change resulted in an unused function parameter to mkdir_rdt_prepare(). Clean up the unused function parameter in mkdir_rdt_prepare() and its callers rdtgroup_mkdir_mon() and rdtgroup_mkdir_ctrl_mon(). Signed-off-by: Xiaochen Shen <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Reviewed-by: Reinette Chatre <[email protected]> Reviewed-by: Tony Luck <[email protected]> Acked-by: Thomas Gleixner <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-01-20x86/resctrl: Fix a deadlock due to inaccurate referenceXiaochen Shen1-8/+8
There is a race condition which results in a deadlock when rmdir and mkdir execute concurrently: $ ls /sys/fs/resctrl/c1/mon_groups/m1/ cpus cpus_list mon_data tasks Thread 1: rmdir /sys/fs/resctrl/c1 Thread 2: mkdir /sys/fs/resctrl/c1/mon_groups/m1 3 locks held by mkdir/48649: #0: (sb_writers#17){.+.+}, at: [<ffffffffb4ca2aa0>] mnt_want_write+0x20/0x50 #1: (&type->i_mutex_dir_key#8/1){+.+.}, at: [<ffffffffb4c8c13b>] filename_create+0x7b/0x170 #2: (rdtgroup_mutex){+.+.}, at: [<ffffffffb4a4389d>] rdtgroup_kn_lock_live+0x3d/0x70 4 locks held by rmdir/48652: #0: (sb_writers#17){.+.+}, at: [<ffffffffb4ca2aa0>] mnt_want_write+0x20/0x50 #1: (&type->i_mutex_dir_key#8/1){+.+.}, at: [<ffffffffb4c8c3cf>] do_rmdir+0x13f/0x1e0 #2: (&type->i_mutex_dir_key#8){++++}, at: [<ffffffffb4c86d5d>] vfs_rmdir+0x4d/0x120 #3: (rdtgroup_mutex){+.+.}, at: [<ffffffffb4a4389d>] rdtgroup_kn_lock_live+0x3d/0x70 Thread 1 is deleting control group "c1". Holding rdtgroup_mutex, kernfs_remove() removes all kernfs nodes under directory "c1" recursively, then waits for sub kernfs node "mon_groups" to drop active reference. Thread 2 is trying to create a subdirectory "m1" in the "mon_groups" directory. The wrapper kernfs_iop_mkdir() takes an active reference to the "mon_groups" directory but the code drops the active reference to the parent directory "c1" instead. As a result, Thread 1 is blocked on waiting for active reference to drop and never release rdtgroup_mutex, while Thread 2 is also blocked on trying to get rdtgroup_mutex. Thread 1 (rdtgroup_rmdir) Thread 2 (rdtgroup_mkdir) (rmdir /sys/fs/resctrl/c1) (mkdir /sys/fs/resctrl/c1/mon_groups/m1) ------------------------- ------------------------- kernfs_iop_mkdir /* * kn: "m1", parent_kn: "mon_groups", * prgrp_kn: parent_kn->parent: "c1", * * "mon_groups", parent_kn->active++: 1 */ kernfs_get_active(parent_kn) kernfs_iop_rmdir /* "c1", kn->active++ */ kernfs_get_active(kn) rdtgroup_kn_lock_live atomic_inc(&rdtgrp->waitcount) /* "c1", kn->active-- */ kernfs_break_active_protection(kn) mutex_lock rdtgroup_rmdir_ctrl free_all_child_rdtgrp sentry->flags = RDT_DELETED rdtgroup_ctrl_remove rdtgrp->flags = RDT_DELETED kernfs_get(kn) kernfs_remove(rdtgrp->kn) __kernfs_remove /* "mon_groups", sub_kn */ atomic_add(KN_DEACTIVATED_BIAS, &sub_kn->active) kernfs_drain(sub_kn) /* * sub_kn->active == KN_DEACTIVATED_BIAS + 1, * waiting on sub_kn->active to drop, but it * never drops in Thread 2 which is blocked * on getting rdtgroup_mutex. */ Thread 1 hangs here ----> wait_event(sub_kn->active == KN_DEACTIVATED_BIAS) ... rdtgroup_mkdir rdtgroup_mkdir_mon(parent_kn, prgrp_kn) mkdir_rdt_prepare(parent_kn, prgrp_kn) rdtgroup_kn_lock_live(prgrp_kn) atomic_inc(&rdtgrp->waitcount) /* * "c1", prgrp_kn->active-- * * The active reference on "c1" is * dropped, but not matching the * actual active reference taken * on "mon_groups", thus causing * Thread 1 to wait forever while * holding rdtgroup_mutex. */ kernfs_break_active_protection( prgrp_kn) /* * Trying to get rdtgroup_mutex * which is held by Thread 1. */ Thread 2 hangs here ----> mutex_lock ... The problem is that the creation of a subdirectory in the "mon_groups" directory incorrectly releases the active protection of its parent directory instead of itself before it starts waiting for rdtgroup_mutex. This is triggered by the rdtgroup_mkdir() flow calling rdtgroup_kn_lock_live()/rdtgroup_kn_unlock() with kernfs node of the parent control group ("c1") as argument. It should be called with kernfs node "mon_groups" instead. What is currently missing is that the kn->priv of "mon_groups" is NULL instead of pointing to the rdtgrp. Fix it by pointing kn->priv to rdtgrp when "mon_groups" is created. Then it could be passed to rdtgroup_kn_lock_live()/rdtgroup_kn_unlock() instead. And then it operates on the same rdtgroup structure but handles the active reference of kernfs node "mon_groups" to prevent deadlock. The same changes are also made to the "mon_data" directories. This results in some unused function parameters that will be cleaned up in follow-up patch as the focus here is on the fix only in support of backporting efforts. Fixes: c7d9aac61311 ("x86/intel_rdt/cqm: Add mkdir support for RDT monitoring") Suggested-by: Reinette Chatre <[email protected]> Signed-off-by: Xiaochen Shen <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Reviewed-by: Reinette Chatre <[email protected]> Reviewed-by: Tony Luck <[email protected]> Acked-by: Thomas Gleixner <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected]
2020-01-20x86/resctrl: Fix use-after-free due to inaccurate refcount of rdtgroupXiaochen Shen1-2/+2
There is a race condition in the following scenario which results in an use-after-free issue when reading a monitoring file and deleting the parent ctrl_mon group concurrently: Thread 1 calls atomic_inc() to take refcount of rdtgrp and then calls kernfs_break_active_protection() to drop the active reference of kernfs node in rdtgroup_kn_lock_live(). In Thread 2, kernfs_remove() is a blocking routine. It waits on all sub kernfs nodes to drop the active reference when removing all subtree kernfs nodes recursively. Thread 2 could block on kernfs_remove() until Thread 1 calls kernfs_break_active_protection(). Only after kernfs_remove() completes the refcount of rdtgrp could be trusted. Before Thread 1 calls atomic_inc() and kernfs_break_active_protection(), Thread 2 could call kfree() when the refcount of rdtgrp (sentry) is 0 instead of 1 due to the race. In Thread 1, in rdtgroup_kn_unlock(), referring to earlier rdtgrp memory (rdtgrp->waitcount) which was already freed in Thread 2 results in use-after-free issue. Thread 1 (rdtgroup_mondata_show) Thread 2 (rdtgroup_rmdir) -------------------------------- ------------------------- rdtgroup_kn_lock_live /* * kn active protection until * kernfs_break_active_protection(kn) */ rdtgrp = kernfs_to_rdtgroup(kn) rdtgroup_kn_lock_live atomic_inc(&rdtgrp->waitcount) mutex_lock rdtgroup_rmdir_ctrl free_all_child_rdtgrp /* * sentry->waitcount should be 1 * but is 0 now due to the race. */ kfree(sentry)*[1] /* * Only after kernfs_remove() * completes, the refcount of * rdtgrp could be trusted. */ atomic_inc(&rdtgrp->waitcount) /* kn->active-- */ kernfs_break_active_protection(kn) rdtgroup_ctrl_remove rdtgrp->flags = RDT_DELETED /* * Blocking routine, wait for * all sub kernfs nodes to drop * active reference in * kernfs_break_active_protection. */ kernfs_remove(rdtgrp->kn) rdtgroup_kn_unlock mutex_unlock atomic_dec_and_test( &rdtgrp->waitcount) && (flags & RDT_DELETED) kernfs_unbreak_active_protection(kn) kfree(rdtgrp) mutex_lock mon_event_read rdtgroup_kn_unlock mutex_unlock /* * Use-after-free: refer to earlier rdtgrp * memory which was freed in [1]. */ atomic_dec_and_test(&rdtgrp->waitcount) && (flags & RDT_DELETED) /* kn->active++ */ kernfs_unbreak_active_protection(kn) kfree(rdtgrp) Fix it by moving free_all_child_rdtgrp() to after kernfs_remove() in rdtgroup_rmdir_ctrl() to ensure it has the accurate refcount of rdtgrp. Fixes: f3cbeacaa06e ("x86/intel_rdt/cqm: Add rmdir support") Suggested-by: Reinette Chatre <[email protected]> Signed-off-by: Xiaochen Shen <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Reviewed-by: Reinette Chatre <[email protected]> Reviewed-by: Tony Luck <[email protected]> Acked-by: Thomas Gleixner <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected]
2020-01-20x86/resctrl: Fix use-after-free when deleting resource groupsXiaochen Shen1-2/+10
A resource group (rdtgrp) contains a reference count (rdtgrp->waitcount) that indicates how many waiters expect this rdtgrp to exist. Waiters could be waiting on rdtgroup_mutex or some work sitting on a task's workqueue for when the task returns from kernel mode or exits. The deletion of a rdtgrp is intended to have two phases: (1) while holding rdtgroup_mutex the necessary cleanup is done and rdtgrp->flags is set to RDT_DELETED, (2) after releasing the rdtgroup_mutex, the rdtgrp structure is freed only if there are no waiters and its flag is set to RDT_DELETED. Upon gaining access to rdtgroup_mutex or rdtgrp, a waiter is required to check for the RDT_DELETED flag. When unmounting the resctrl file system or deleting ctrl_mon groups, all of the subdirectories are removed and the data structure of rdtgrp is forcibly freed without checking rdtgrp->waitcount. If at this point there was a waiter on rdtgrp then a use-after-free issue occurs when the waiter starts running and accesses the rdtgrp structure it was waiting on. See kfree() calls in [1], [2] and [3] in these two call paths in following scenarios: (1) rdt_kill_sb() -> rmdir_all_sub() -> free_all_child_rdtgrp() (2) rdtgroup_rmdir() -> rdtgroup_rmdir_ctrl() -> free_all_child_rdtgrp() There are several scenarios that result in use-after-free issue in following: Scenario 1: ----------- In Thread 1, rdtgroup_tasks_write() adds a task_work callback move_myself(). If move_myself() is scheduled to execute after Thread 2 rdt_kill_sb() is finished, referring to earlier rdtgrp memory (rdtgrp->waitcount) which was already freed in Thread 2 results in use-after-free issue. Thread 1 (rdtgroup_tasks_write) Thread 2 (rdt_kill_sb) ------------------------------- ---------------------- rdtgroup_kn_lock_live atomic_inc(&rdtgrp->waitcount) mutex_lock rdtgroup_move_task __rdtgroup_move_task /* * Take an extra refcount, so rdtgrp cannot be freed * before the call back move_myself has been invoked */ atomic_inc(&rdtgrp->waitcount) /* Callback move_myself will be scheduled for later */ task_work_add(move_myself) rdtgroup_kn_unlock mutex_unlock atomic_dec_and_test(&rdtgrp->waitcount) && (flags & RDT_DELETED) mutex_lock rmdir_all_sub /* * sentry and rdtgrp are freed * without checking refcount */ free_all_child_rdtgrp kfree(sentry)*[1] kfree(rdtgrp)*[2] mutex_unlock /* * Callback is scheduled to execute * after rdt_kill_sb is finished */ move_myself /* * Use-after-free: refer to earlier rdtgrp * memory which was freed in [1] or [2]. */ atomic_dec_and_test(&rdtgrp->waitcount) && (flags & RDT_DELETED) kfree(rdtgrp) Scenario 2: ----------- In Thread 1, rdtgroup_tasks_write() adds a task_work callback move_myself(). If move_myself() is scheduled to execute after Thread 2 rdtgroup_rmdir() is finished, referring to earlier rdtgrp memory (rdtgrp->waitcount) which was already freed in Thread 2 results in use-after-free issue. Thread 1 (rdtgroup_tasks_write) Thread 2 (rdtgroup_rmdir) ------------------------------- ------------------------- rdtgroup_kn_lock_live atomic_inc(&rdtgrp->waitcount) mutex_lock rdtgroup_move_task __rdtgroup_move_task /* * Take an extra refcount, so rdtgrp cannot be freed * before the call back move_myself has been invoked */ atomic_inc(&rdtgrp->waitcount) /* Callback move_myself will be scheduled for later */ task_work_add(move_myself) rdtgroup_kn_unlock mutex_unlock atomic_dec_and_test(&rdtgrp->waitcount) && (flags & RDT_DELETED) rdtgroup_kn_lock_live atomic_inc(&rdtgrp->waitcount) mutex_lock rdtgroup_rmdir_ctrl free_all_child_rdtgrp /* * sentry is freed without * checking refcount */ kfree(sentry)*[3] rdtgroup_ctrl_remove rdtgrp->flags = RDT_DELETED rdtgroup_kn_unlock mutex_unlock atomic_dec_and_test( &rdtgrp->waitcount) && (flags & RDT_DELETED) kfree(rdtgrp) /* * Callback is scheduled to execute * after rdt_kill_sb is finished */ move_myself /* * Use-after-free: refer to earlier rdtgrp * memory which was freed in [3]. */ atomic_dec_and_test(&rdtgrp->waitcount) && (flags & RDT_DELETED) kfree(rdtgrp) If CONFIG_DEBUG_SLAB=y, Slab corruption on kmalloc-2k can be observed like following. Note that "0x6b" is POISON_FREE after kfree(). The corrupted bits "0x6a", "0x64" at offset 0x424 correspond to waitcount member of struct rdtgroup which was freed: Slab corruption (Not tainted): kmalloc-2k start=ffff9504c5b0d000, len=2048 420: 6b 6b 6b 6b 6a 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkjkkkkkkkkkkk Single bit error detected. Probably bad RAM. Run memtest86+ or a similar memory test tool. Next obj: start=ffff9504c5b0d800, len=2048 000: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk 010: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Slab corruption (Not tainted): kmalloc-2k start=ffff9504c58ab800, len=2048 420: 6b 6b 6b 6b 64 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkdkkkkkkkkkkk Prev obj: start=ffff9504c58ab000, len=2048 000: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk 010: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Fix this by taking reference count (waitcount) of rdtgrp into account in the two call paths that currently do not do so. Instead of always freeing the resource group it will only be freed if there are no waiters on it. If there are waiters, the resource group will have its flags set to RDT_DELETED. It will be left to the waiter to free the resource group when it starts running and finding that it was the last waiter and the resource group has been removed (rdtgrp->flags & RDT_DELETED) since. (1) rdt_kill_sb() -> rmdir_all_sub() -> free_all_child_rdtgrp() (2) rdtgroup_rmdir() -> rdtgroup_rmdir_ctrl() -> free_all_child_rdtgrp() Fixes: f3cbeacaa06e ("x86/intel_rdt/cqm: Add rmdir support") Fixes: 60cf5e101fd4 ("x86/intel_rdt: Add mkdir to resctrl file system") Suggested-by: Reinette Chatre <[email protected]> Signed-off-by: Xiaochen Shen <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Reviewed-by: Reinette Chatre <[email protected]> Reviewed-by: Tony Luck <[email protected]> Acked-by: Thomas Gleixner <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected]
2020-01-20x86/cpu: Remove redundant cpu_detect_cache_sizes() callTony W Wang-oc2-4/+0
Both functions call init_intel_cacheinfo() which computes L2 and L3 cache sizes from CPUID(4). But then they also call cpu_detect_cache_sizes() a bit later which computes ->x86_tlbsize and L2 size from CPUID(80000006). However, the latter call is not needed because - on these CPUs, CPUID(80000006).EBX for ->x86_tlbsize is reserved - CPUID(80000006).ECX for the L2 size has the same result as CPUID(4) Therefore, remove the latter call to simplify the code. [ bp: Rewrite commit message. ] Signed-off-by: Tony W Wang-oc <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-01-20x86/resctrl: Add task resctrl information displayChen Yu1-0/+86
Monitoring tools that want to find out which resctrl control and monitor groups a task belongs to must currently read the "tasks" file in every group until they locate the process ID. Add an additional file /proc/{pid}/cpu_resctrl_groups to provide this information: 1) res: mon: resctrl is not available. 2) res:/ mon: Task is part of the root resctrl control group, and it is not associated to any monitor group. 3) res:/ mon:mon0 Task is part of the root resctrl control group and monitor group mon0. 4) res:group0 mon: Task is part of resctrl control group group0, and it is not associated to any monitor group. 5) res:group0 mon:mon1 Task is part of resctrl control group group0 and monitor group mon1. Signed-off-by: Chen Yu <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Tested-by: Jinshi Chen <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-01-20Merge tag 'v5.5-rc7' into locking/kcsan, to refresh the treeIngo Molnar4-10/+11
Signed-off-by: Ingo Molnar <[email protected]>
2020-01-20Merge tag 'v5.5-rc7' into efi/core, to pick up fixesIngo Molnar4-10/+11
Signed-off-by: Ingo Molnar <[email protected]>
2020-01-18Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds3-6/+6
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "Misc fixes: - a resctrl fix for uninitialized objects found by debugobjects - a resctrl memory leak fix - fix the unintended re-enabling of the of SME and SEV CPU flags if memory encryption was disabled at bootup via the MSR space" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/CPU/AMD: Ensure clearing of SME/SEV features is maintained x86/resctrl: Fix potential memory leak x86/resctrl: Fix an imbalance in domain_remove_cpu()
2020-01-17x86/resctrl: Check monitoring static key in the MBM overflow handlerXiaochen Shen2-2/+3
Currently, there are three static keys in the resctrl file system: rdt_mon_enable_key and rdt_alloc_enable_key indicate if the monitoring feature and the allocation feature are enabled, respectively. The rdt_enable_key is enabled when either the monitoring feature or the allocation feature is enabled. If no monitoring feature is present (either hardware doesn't support a monitoring feature or the feature is disabled by the kernel command line option "rdt="), rdt_enable_key is still enabled but rdt_mon_enable_key is disabled. MBM is a monitoring feature. The MBM overflow handler intends to check if the monitoring feature is not enabled for fast return. So check the rdt_mon_enable_key in it instead of the rdt_enable_key as former is the more accurate check. [ bp: Massage commit message. ] Fixes: e33026831bdb ("x86/intel_rdt/mbm: Handle counter overflow") Signed-off-by: Xiaochen Shen <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-01-17x86/speculation/swapgs: Exclude Zhaoxin CPUs from SWAPGS vulnerabilityTony W Wang-oc1-2/+2
New Zhaoxin family 7 CPUs are not affected by the SWAPGS vulnerability. So mark these CPUs in the cpu vulnerability whitelist accordingly. Signed-off-by: Tony W Wang-oc <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-01-17x86/speculation/spectre_v2: Exclude Zhaoxin CPUs from SPECTRE_V2Tony W Wang-oc1-1/+8
New Zhaoxin family 7 CPUs are not affected by SPECTRE_V2. So define a separate cpu_vuln_whitelist bit NO_SPECTRE_V2 and add these CPUs to the cpu vulnerability whitelist. Signed-off-by: Tony W Wang-oc <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-01-17x86/cpu: Update cached HLE state on write to TSX_CTRL_CPUID_CLEARPawan Gupta1-6/+7
/proc/cpuinfo currently reports Hardware Lock Elision (HLE) feature to be present on boot cpu even if it was disabled during the bootup. This is because cpuinfo_x86->x86_capability HLE bit is not updated after TSX state is changed via the new MSR IA32_TSX_CTRL. Update the cached HLE bit also since it is expected to change after an update to CPUID_CLEAR bit in MSR IA32_TSX_CTRL. Fixes: 95c5824f75f3 ("x86/cpu: Add a "tsx=" cmdline option with TSX disabled by default") Signed-off-by: Pawan Gupta <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Tested-by: Neelima Krishnan <[email protected]> Reviewed-by: Dave Hansen <[email protected]> Reviewed-by: Josh Poimboeuf <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/2529b99546294c893dfa1c89e2b3e46da3369a59.1578685425.git.pawan.kumar.gupta@linux.intel.com
2020-01-16x86/CPU/AMD: Ensure clearing of SME/SEV features is maintainedTom Lendacky1-2/+2
If the SME and SEV features are present via CPUID, but memory encryption support is not enabled (MSR 0xC001_0010[23]), the feature flags are cleared using clear_cpu_cap(). However, if get_cpu_cap() is later called, these feature flags will be reset back to present, which is not desired. Change from using clear_cpu_cap() to setup_clear_cpu_cap() so that the clearing of the flags is maintained. Signed-off-by: Tom Lendacky <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Cc: <[email protected]> # 4.16.x- Link: https://lkml.kernel.org/r/226de90a703c3c0be5a49565047905ac4e94e8f3.1579125915.git.thomas.lendacky@amd.com
2020-01-16x86/MCE/AMD, EDAC/mce_amd: Add new Load Store unit McaTypeYazen Ghannam1-0/+2
Add support for a new version of the Load Store unit bank type as indicated by its McaType value, which will be present in future SMCA systems. Add the new (HWID, MCATYPE) tuple. Reuse the same name, since this is logically the same to the user. Also, add the new error descriptions to edac_mce_amd. Signed-off-by: Yazen Ghannam <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-01-15x86/cpu: Print "VMX disabled" error message iff KVM is enabledSean Christopherson1-2/+3
Don't print an error message about VMX being disabled by BIOS if KVM, the sole user of VMX, is disabled. E.g. if KVM is disabled and the MSR is unlocked, the kernel will intentionally disable VMX when locking feature control and then complain that "BIOS" disabled VMX. Fixes: ef4d3bf19855 ("x86/cpu: Clear VMX feature flag if VMX is not fully enabled") Signed-off-by: Sean Christopherson <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-01-15x86/mce/therm_throt: Do not access uninitialized therm_workChuansheng Liu1-4/+5
It is relatively easy to trigger the following boot splat on an Ice Lake client platform. The call stack is like: kernel BUG at kernel/timer/timer.c:1152! Call Trace: __queue_delayed_work queue_delayed_work_on therm_throt_process intel_thermal_interrupt ... The reason is that a CPU's thermal interrupt is enabled prior to executing its hotplug onlining callback which will initialize the throttling workqueues. Such a race can lead to therm_throt_process() accessing an uninitialized therm_work, leading to the above BUG at a very early bootup stage. Therefore, unmask the thermal interrupt vector only after having setup the workqueues completely. [ bp: Heavily massage commit message and correct comment formatting. ] Fixes: f6656208f04e ("x86/mce/therm_throt: Optimize notifications of thermal throttle") Signed-off-by: Chuansheng Liu <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Acked-by: Tony Luck <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-01-13x86/cpufeatures: Add flag to track whether MSR IA32_FEAT_CTL is configuredSean Christopherson1-0/+2
Add a new feature flag, X86_FEATURE_MSR_IA32_FEAT_CTL, to track whether IA32_FEAT_CTL has been initialized. This will allow KVM, and any future subsystems that depend on IA32_FEAT_CTL, to rely purely on cpufeatures to query platform support, e.g. allows a future patch to remove KVM's manual IA32_FEAT_CTL MSR checks. Various features (on platforms that support IA32_FEAT_CTL) are dependent on IA32_FEAT_CTL being configured and locked, e.g. VMX and LMCE. The MSR is always configured during boot, but only if the CPU vendor is recognized by the kernel. Because CPUID doesn't incorporate the current IA32_FEAT_CTL value in its reporting of relevant features, it's possible for a feature to be reported as supported in cpufeatures but not truly enabled, e.g. if the CPU supports VMX but the kernel doesn't recognize the CPU. As a result, without the flag, KVM would see VMX as supported even if IA32_FEAT_CTL hasn't been initialized, and so would need to manually read the MSR and check the various enabling bits to avoid taking an unexpected #GP on VMXON. Signed-off-by: Sean Christopherson <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-01-13x86/cpu: Set synthetic VMX cpufeatures during init_ia32_feat_ctl()Sean Christopherson4-119/+14
Set the synthetic VMX cpufeatures, which need to be kept to preserve /proc/cpuinfo's ABI, in the common IA32_FEAT_CTL initialization code. Remove the vendor code that manually sets the synthetic flags. Signed-off-by: Sean Christopherson <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Link: https://lkml.kernel.org/r/[email protected]