wireguard-linux/arch/x86/kernel/cpu/mce/internal.h, branch jd/orphan-parallel

x86/mce: Pass pointer to saved pt_regs to severity calculation routines

2020-10-07T08:51:42Z

New recovery features require additional information about processor state when a machine check occurred. Pass pt_regs down to the routines that need it. No functional change. Signed-off-by: Youquan Song Signed-off-by: Tony Luck Signed-off-by: Borislav Petkov Link: https://lkml.kernel.org/r/20201006210910.21062-2-tony.luck@intel.com

x86/mce: Make mce_rdmsrl() panic on an inaccessible MSR

2020-09-11T06:25:43Z

If an exception needs to be handled while reading an MSR - which is in most of the cases caused by a #GP on a non-existent MSR - then this is most likely the incarnation of a BIOS or a hardware bug. Such bug violates the architectural guarantee that MCA banks are present with all MSRs belonging to them. The proper fix belongs in the hardware/firmware - not in the kernel. Handling an #MC exception which is raised while an NMI is being handled would cause the nasty NMI nesting issue because of the shortcoming of IRET of reenabling NMIs when executed. And the machine is in an #MC context already so be at its side. Tracing MSR accesses while in #MC is another no-no due to tracing being inherently a bad idea in atomic context: vmlinux.o: warning: objtool: do_machine_check()+0x4a: call to mce_rdmsrl() leaves .noinstr.text section so remove all that "additional" functionality from mce_rdmsrl() and provide it with a special exception handler which panics the machine when that MSR is not accessible. The exception handler prints a human-readable message explaining what the panic reason is but, what is more, it panics while in the #GP handler and latter won't have executed an IRET, thus opening the NMI nesting issue in the case when the #MC has happened while handling an NMI. (#MC itself won't be reenabled until MCG_STATUS hasn't been cleared). Suggested-by: Andy Lutomirski Suggested-by: Peter Zijlstra [ Add missing prototypes for ex_handler_* ] Reported-by: kernel test robot Signed-off-by: Borislav Petkov Reviewed-by: Tony Luck Link: https://lkml.kernel.org/r/20200906212130.GA28456@zn.tnic

Merge branch 'x86/entry' into ras/core

2020-06-11T13:17:57Z

to fixup conflicts in arch/x86/kernel/cpu/mce/core.c so MCE specific follow up patches can be applied without creating a horrible merge conflict afterwards.

x86/entry: Convert Machine Check to IDTENTRY_IST

2020-06-11T13:14:57Z

Convert #MC to IDTENTRY_MCE: - Implement the C entry points with DEFINE_IDTENTRY_MCE - Emit the ASM stub with DECLARE_IDTENTRY_MCE - Remove the ASM idtentry in 64bit - Remove the open coded ASM entry code in 32bit - Fixup the XEN/PV code - Remove the old prototypes - Remove the error code from *machine_check_vector() as it is always 0 and not used by any of the functions it can point to. Fixup all the functions as well. No functional change. Signed-off-by: Thomas Gleixner Reviewed-by: Alexandre Chartre Acked-by: Peter Zijlstra Acked-by: Andy Lutomirski Link: https://lkml.kernel.org/r/20200505135314.334980426@linutronix.de

x86/mce: Add mce=print_all option

2020-04-14T14:00:30Z

Sometimes, when logs are getting lost, it's nice to just have everything dumped to the serial console. Signed-off-by: Tony Luck Signed-off-by: Borislav Petkov Tested-by: Tony Luck Link: https://lkml.kernel.org/r/20200214222720.13168-7-tony.luck@intel.com

x86/mce/amd: Init thresholding machinery only on relevant vendors

2020-04-14T13:47:11Z

... and not unconditionally. [ bp: Add a new vendor_flags bit for that. ] Signed-off-by: Thomas Gleixner Signed-off-by: Borislav Petkov Link: https://lkml.kernel.org/r/20200403161943.1458-3-bp@alien8.de

Merge tag 'x86-entry-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2020-03-31T02:14:28Z

Pull x86 entry code updates from Thomas Gleixner: - Convert the 32bit syscalls to be pt_regs based which removes the requirement to push all 6 potential arguments onto the stack and consolidates the interface with the 64bit variant - The first small portion of the exception and syscall related entry code consolidation which aims to address the recently discovered issues vs. RCU, int3, NMI and some other exceptions which can interrupt any context. The bulk of the changes is still work in progress and aimed for 5.8. - A few lockdep namespace cleanups which have been applied into this branch to keep the prerequisites for the ongoing work confined. * tag 'x86-entry-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (35 commits) x86/entry: Fix build error x86 with !CONFIG_POSIX_TIMERS lockdep: Rename trace_{hard,soft}{irq_context,irqs_enabled}() lockdep: Rename trace_softirqs_{on,off}() lockdep: Rename trace_hardirq_{enter,exit}() x86/entry: Rename ___preempt_schedule x86: Remove unneeded includes x86/entry: Drop asmlinkage from syscalls x86/entry/32: Enable pt_regs based syscalls x86/entry/32: Use IA32-specific wrappers for syscalls taking 64-bit arguments x86/entry/32: Rename 32-bit specific syscalls x86/entry/32: Clean up syscall_32.tbl x86/entry: Remove ABI prefixes from functions in syscall tables x86/entry/64: Add __SYSCALL_COMMON() x86/entry: Remove syscall qualifier support x86/entry/64: Remove ptregs qualifier from syscall table x86/entry: Move max syscall number calculation to syscallhdr.sh x86/entry/64: Split X32 syscall table into its own file x86/entry/64: Move sys_ni_syscall stub to common.c x86/entry/64: Use syscall wrappers for x32_rt_sigreturn x86/entry: Refactor SYS_NI macros ...

x86/entry/32: Force MCE through do_mce()

2020-02-27T13:48:39Z

Remove the pointless difference between 32 and 64 bit to make further unifications simpler. Signed-off-by: Thomas Gleixner Reviewed-by: Frederic Weisbecker Reviewed-by: Alexandre Chartre Reviewed-by: Andy Lutomirski Link: https://lkml.kernel.org/r/20200225220216.428188397@linutronix.de

x86/mce: Do not log spurious corrected mce errors

2020-02-19T17:14:49Z

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 Signed-off-by: Alexander Krupp Signed-off-by: Prarit Bhargava Signed-off-by: Borislav Petkov Link: https://bugzilla.kernel.org/show_bug.cgi?id=206587 Link: https://lkml.kernel.org/r/20200219131611.36816-1-prarit@redhat.com

x86/mce: Remove mce_inject_log() in favor of mce_log()

2019-12-17T09:26:41Z

The mutex in mce_inject_log() became unnecessary with commit 5de97c9f6d85 ("x86/mce: Factor out and deprecate the /dev/mcelog driver"), though the original reason for its presence only vanished with commit 7298f08ea887 ("x86/mcelog: Get rid of RCU remnants"). Drop the mutex. And as that makes mce_inject_log() identical to mce_log(), get rid of the former in favor of the latter. Signed-off-by: Jan H. Schönherr Signed-off-by: Borislav Petkov Reviewed-by: Tony Luck Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: linux-edac Cc: Thomas Gleixner Cc: x86-ml Link: https://lkml.kernel.org/r/20191210000733.17979-7-jschoenh@amazon.de