BMC/Intel-BMC/linux.git/arch/x86/kernel/cpu/mcheck, branch dev-4.17

x86/MCE: Remove min interval polling limitation

2018-07-25T09:26:07+00:00

commit fbdb328c6bae0a7c78d75734a738b66b86dffc96 upstream. commit b3b7c4795c ("x86/MCE: Serialize sysfs changes") introduced a min interval limitation when setting the check interval for polled MCEs. However, the logic is that 0 disables polling for corrected MCEs, see Documentation/x86/x86_64/machinecheck. The limitation prevents disabling. Remove this limitation and allow the value 0 to disable polling again. Fixes: b3b7c4795c ("x86/MCE: Serialize sysfs changes") Signed-off-by: Dewet Thibaut Signed-off-by: Alexander Sverdlin [ Massage commit message. ] Signed-off-by: Borislav Petkov Signed-off-by: Thomas Gleixner Cc: Tony Luck Cc: linux-edac Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20180716084927.24869-1-alexander.sverdlin@nokia.com Signed-off-by: Greg Kroah-Hartman

x86/mce: Do not overwrite MCi_STATUS in mce_no_way_out()

2018-07-03T09:26:45+00:00

commit 1f74c8a64798e2c488f86efc97e308b85fb7d7aa upstream. mce_no_way_out() does a quick check during #MC to see whether some of the MCEs logged would require the kernel to panic immediately. And it passes a struct mce where MCi_STATUS gets written. However, after having saved a valid status value, the next iteration of the loop which goes over the MCA banks on the CPU, overwrites the valid status value because we're using struct mce as storage instead of a temporary variable. Which leads to MCE records with an empty status value: mce: [Hardware Error]: CPU 0: Machine Check Exception: 6 Bank 0: 0000000000000000 mce: [Hardware Error]: RIP 10: {trigger_mce+0x7/0x10} In order to prevent the loss of the status register value, return immediately when severity is a panic one so that we can panic immediately with the first fatal MCE logged. This is also the intention of this function and not to noodle over the banks while a fatal MCE is already logged. Tony: read the rest of the MCA bank to populate the struct mce fully. Suggested-by: Tony Luck Signed-off-by: Borislav Petkov Signed-off-by: Thomas Gleixner Cc: Link: https://lkml.kernel.org/r/20180622095428.626-8-bp@alien8.de Signed-off-by: Greg Kroah-Hartman

x86/mce: Fix incorrect "Machine check from unknown source" message

2018-07-03T09:26:44+00:00

commit 40c36e2741d7fe1e66d6ec55477ba5fd19c9c5d2 upstream. Some injection testing resulted in the following console log: mce: [Hardware Error]: CPU 22: Machine Check Exception: f Bank 1: bd80000000100134 mce: [Hardware Error]: RIP 10: {pmem_do_bvec+0x11d/0x330 [nd_pmem]} mce: [Hardware Error]: TSC c51a63035d52 ADDR 3234bc4000 MISC 88 mce: [Hardware Error]: PROCESSOR 0:50654 TIME 1526502199 SOCKET 0 APIC 38 microcode 2000043 mce: [Hardware Error]: Run the above through 'mcelog --ascii' Kernel panic - not syncing: Machine check from unknown source This confused everybody because the first line quite clearly shows that we found a logged error in "Bank 1", while the last line says "unknown source". The problem is that the Linux code doesn't do the right thing for a local machine check that results in a fatal error. It turns out that we know very early in the handler whether the machine check is fatal. The call to mce_no_way_out() has checked all the banks for the CPU that took the local machine check. If it says we must crash, we can do so right away with the right messages. We do scan all the banks again. This means that we might initially not see a problem, but during the second scan find something fatal. If this happens we print a slightly different message (so I can see if it actually every happens). [ bp: Remove unneeded severity assignment. ] Signed-off-by: Tony Luck Signed-off-by: Borislav Petkov Signed-off-by: Thomas Gleixner Cc: Ashok Raj Cc: Dan Williams Cc: Qiuxu Zhuo Cc: linux-edac Cc: stable@vger.kernel.org # 4.2 Link: http://lkml.kernel.org/r/52e049a497e86fd0b71c529651def8871c804df0.1527283897.git.tony.luck@intel.com Signed-off-by: Greg Kroah-Hartman

x86/mce: Improve error message when kernel cannot recover

2018-07-03T09:26:44+00:00

commit c7d606f560e4c698884697fef503e4abacdd8c25 upstream. Since we added support to add recovery from some errors inside the kernel in: commit b2f9d678e28c ("x86/mce: Check for faults tagged in EXTABLE_CLASS_FAULT exception table entries") we have done a less than stellar job at reporting the cause of recoverable machine checks that occur in other parts of the kernel. The user just gets the unhelpful message: mce: [Hardware Error]: Machine check: Action required: unknown MCACOD doubly unhelpful when they check the manual for the reported IA32_MSR_STATUS.MCACOD and see that it is listed as one of the standard recoverable values. Add an extra rule to the MCE severity table to catch this case and report it as: mce: [Hardware Error]: Machine check: Data load in unrecoverable area of kernel Fixes: b2f9d678e28c ("x86/mce: Check for faults tagged in EXTABLE_CLASS_FAULT exception table entries") Signed-off-by: Tony Luck Signed-off-by: Thomas Gleixner Cc: Qiuxu Zhuo Cc: Ashok Raj Cc: stable@vger.kernel.org # 4.6+ Cc: Dan Williams Cc: Borislav Petkov Link: https://lkml.kernel.org/r/4cc7c465150a9a48b8b9f45d0b840278e77eb9b5.1527283897.git.tony.luck@intel.com Signed-off-by: Greg Kroah-Hartman

x86/MCE: Fix stack out-of-bounds write in mce-inject.c: Flags_read()

2018-06-25T23:51:25+00:00

commit 985c78d3ff8e9c74450fa2bb08eb55e680d999ca upstream. Each of the strings that we want to put into the buf[MAX_FLAG_OPT_SIZE] in flags_read() is two characters long. But the sprintf() adds a trailing newline and will add a terminating NUL byte. So MAX_FLAG_OPT_SIZE needs to be 4. sprintf() calls vsnprintf() and *that* does return: " * The return value is the number of characters which would * be generated for the given input, excluding the trailing * '\0', as per ISO C99." Note the "excluding". Reported-by: Dmitry Vyukov Signed-off-by: Tony Luck Signed-off-by: Borislav Petkov Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Cc: linux-edac Link: http://lkml.kernel.org/r/20180427163707.ktaiysvbk3yhk4wm@agluck-desk Signed-off-by: Greg Kroah-Hartman

x86/MCE/AMD: Cache SMCA MISC block addresses

2018-05-19T13:19:30+00:00

... into a global, two-dimensional array and service subsequent reads from that cache to avoid rdmsr_on_cpu() calls during CPU hotplug (IPIs with IRQs disabled). In addition, this fixes a KASAN slab-out-of-bounds read due to wrong usage of the bank->blocks pointer. Fixes: 27bd59502702 ("x86/mce/AMD: Get address from already initialized block") Reported-by: Johannes Hirte Tested-by: Johannes Hirte Signed-off-by: Borislav Petkov Signed-off-by: Thomas Gleixner Cc: Yazen Ghannam Link: http://lkml.kernel.org/r/20180414004230.GA2033@probook

Merge branch 'x86-timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2018-04-02T23:18:31+00:00

Pull x86 timer updates from Ingo Molnar: "Two changes: add the new convert_art_ns_to_tsc() API for upcoming Intel Goldmont+ drivers, and remove the obsolete rdtscll() API" * 'x86-timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/tsc: Get rid of rdtscll() x86/tsc: Convert ART in nanoseconds to TSC

Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2018-04-02T22:45:30+00:00

Pull x86 mm updates from Ingo Molnar: - Extend the memmap= boot parameter syntax to allow the redeclaration and dropping of existing ranges, and to support all e820 range types (Jan H. Schönherr) - Improve the W+X boot time security checks to remove false positive warnings on Xen (Jan Beulich) - Support booting as Xen PVH guest (Juergen Gross) - Improved 5-level paging (LA57) support, in particular it's possible now to have a single kernel image for both 4-level and 5-level hardware (Kirill A. Shutemov) - AMD hardware RAM encryption support (SME/SEV) fixes (Tom Lendacky) - Preparatory commits for hardware-encrypted RAM support on Intel CPUs. (Kirill A. Shutemov) - Improved Intel-MID support (Andy Shevchenko) - Show EFI page tables in page_tables debug files (Andy Lutomirski) - ... plus misc fixes and smaller cleanups * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (56 commits) x86/cpu/tme: Fix spelling: "configuation" -> "configuration" x86/boot: Fix SEV boot failure from change to __PHYSICAL_MASK_SHIFT x86/mm: Update comment in detect_tme() regarding x86_phys_bits x86/mm/32: Remove unused node_memmap_size_bytes() & CONFIG_NEED_NODE_MEMMAP_SIZE logic x86/mm: Remove pointless checks in vmalloc_fault x86/platform/intel-mid: Add special handling for ACPI HW reduced platforms ACPI, x86/boot: Introduce the ->reduced_hw_early_init() ACPI callback ACPI, x86/boot: Split out acpi_generic_reduce_hw_init() and export x86/pconfig: Provide defines and helper to run MKTME_KEY_PROG leaf x86/pconfig: Detect PCONFIG targets x86/tme: Detect if TME and MKTME is activated by BIOS x86/boot/compressed/64: Handle 5-level paging boot if kernel is above 4G x86/boot/compressed/64: Use page table in trampoline memory x86/boot/compressed/64: Use stack from trampoline memory x86/boot/compressed/64: Make sure we have a 32-bit code segment x86/mm: Do not use paravirtualized calls in native_set_p4d() kdump, vmcoreinfo: Export pgtable_l5_enabled value x86/boot/compressed/64: Prepare new top-level page table for trampoline x86/boot/compressed/64: Set up trampoline memory x86/boot/compressed/64: Save and restore trampoline memory ...

Revert "x86/mce/AMD: Collect error info even if valid bits are not set"

2018-03-28T18:34:59+00:00

This reverts commit 4b1e84276a6172980c5bf39aa091ba13e90d6dad. Software uses the valid bits to decide if the values can be used for further processing or other actions. So setting the valid bits will have software act on values that it shouldn't be acting on. The recommendation to save all the register values does not mean that the values are always valid. Signed-off-by: Yazen Ghannam Signed-off-by: Thomas Gleixner Cc: tony.luck@intel.com Cc: Yazen Ghannam Cc: bp@suse.de Cc: linux-edac@vger.kernel.org Link: https://lkml.kernel.org/r/20180326191526.64314-1-Yazen.Ghannam@amd.com

x86/tsc: Get rid of rdtscll()

2018-03-23T19:07:54+00:00

Commit 99770737ca7e ("x86/asm/tsc: Add rdtscll() merge helper") added rdtscll() in August 2015 along with the comment: /* Deprecated, keep it for a cycle for easier merging: */ 12 cycles later it's really overdue for removal. Signed-off-by: Thomas Gleixner