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2018-04-12x86/microcode: Fix CPU synchronization routineBorislav Petkov
commit bb8c13d61a629276a162c1d2b1a20a815cbcfbb7 upstream. Emanuel reported an issue with a hang during microcode update because my dumb idea to use one atomic synchronization variable for both rendezvous - before and after update - was simply bollocks: microcode: microcode_reload_late: late_cpus: 4 microcode: __reload_late: cpu 2 entered microcode: __reload_late: cpu 1 entered microcode: __reload_late: cpu 3 entered microcode: __reload_late: cpu 0 entered microcode: __reload_late: cpu 1 left microcode: Timeout while waiting for CPUs rendezvous, remaining: 1 CPU1 above would finish, leave and the others will still spin waiting for it to join. So do two synchronization atomics instead, which makes the code a lot more straightforward. Also, since the update is serialized and it also takes quite some time per microcode engine, increase the exit timeout by the number of CPUs on the system. That's ok because the moment all CPUs are done, that timeout will be cut short. Furthermore, panic when some of the CPUs timeout when returning from a microcode update: we can't allow a system with not all cores updated. Also, as an optimization, do not do the exit sync if microcode wasn't updated. Reported-by: Emanuel Czirai <xftroxgpx@protonmail.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Emanuel Czirai <xftroxgpx@protonmail.com> Tested-by: Ashok Raj <ashok.raj@intel.com> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lkml.kernel.org/r/20180314183615.17629-2-bp@alien8.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-12x86/microcode: Attempt late loading only when new microcode is presentBorislav Petkov
commit 2613f36ed965d0e5a595a1d931fd3b480e82d6fd upstream. Return UCODE_NEW from the scanning functions to denote that new microcode was found and only then attempt the expensive synchronization dance. Reported-by: Emanuel Czirai <xftroxgpx@protonmail.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Emanuel Czirai <xftroxgpx@protonmail.com> Tested-by: Ashok Raj <ashok.raj@intel.com> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lkml.kernel.org/r/20180314183615.17629-1-bp@alien8.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-12x86/microcode: Synchronize late microcode loadingAshok Raj
commit a5321aec6412b20b5ad15db2d6b916c05349dbff upstream. Original idea by Ashok, completely rewritten by Borislav. Before you read any further: the early loading method is still the preferred one and you should always do that. The following patch is improving the late loading mechanism for long running jobs and cloud use cases. Gather all cores and serialize the microcode update on them by doing it one-by-one to make the late update process as reliable as possible and avoid potential issues caused by the microcode update. [ Borislav: Rewrite completely. ] Co-developed-by: Borislav Petkov <bp@suse.de> Signed-off-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Ashok Raj <ashok.raj@intel.com> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com> Link: https://lkml.kernel.org/r/20180228102846.13447-8-bp@alien8.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-12x86/microcode: Request microcode on the BSPBorislav Petkov
commit cfb52a5a09c8ae3a1dafb44ce549fde5b69e8117 upstream. ... so that any newer version can land in the cache and can later be fished out by the application functions. Do that before grabbing the hotplug lock. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Ashok Raj <ashok.raj@intel.com> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com> Link: https://lkml.kernel.org/r/20180228102846.13447-7-bp@alien8.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-12x86/microcode/intel: Look into the patch cache firstBorislav Petkov
commit d8c3b52c00a05036e0a6b315b4b17921a7b67997 upstream. The cache might contain a newer patch - look in there first. A follow-on change will make sure newest patches are loaded into the cache of microcode patches. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Ashok Raj <ashok.raj@intel.com> Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com> Link: https://lkml.kernel.org/r/20180228102846.13447-6-bp@alien8.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-12x86/microcode: Do not upload microcode if CPUs are offlineAshok Raj
commit 30ec26da9967d0d785abc24073129a34c3211777 upstream. Avoid loading microcode if any of the CPUs are offline, and issue a warning. Having different microcode revisions on the system at any time is outright dangerous. [ Borislav: Massage changelog. ] Signed-off-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Ashok Raj <ashok.raj@intel.com> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com> Link: http://lkml.kernel.org/r/1519352533-15992-4-git-send-email-ashok.raj@intel.com Link: https://lkml.kernel.org/r/20180228102846.13447-5-bp@alien8.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-12x86/microcode/intel: Writeback and invalidate caches before updating microcodeAshok Raj
commit 91df9fdf51492aec9fed6b4cbd33160886740f47 upstream. Updating microcode is less error prone when caches have been flushed and depending on what exactly the microcode is updating. For example, some of the issues around certain Broadwell parts can be addressed by doing a full cache flush. [ Borislav: Massage it and use native_wbinvd() in both cases. ] Signed-off-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Ashok Raj <ashok.raj@intel.com> Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com> Link: http://lkml.kernel.org/r/1519352533-15992-3-git-send-email-ashok.raj@intel.com Link: https://lkml.kernel.org/r/20180228102846.13447-4-bp@alien8.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-12x86/microcode/intel: Check microcode revision before updating sibling threadsAshok Raj
commit c182d2b7d0ca48e0d6ff16f7d883161238c447ed upstream. After updating microcode on one of the threads of a core, the other thread sibling automatically gets the update since the microcode resources on a hyperthreaded core are shared between the two threads. Check the microcode revision on the CPU before performing a microcode update and thus save us the WRMSR 0x79 because it is a particularly expensive operation. [ Borislav: Massage changelog and coding style. ] Signed-off-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Ashok Raj <ashok.raj@intel.com> Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com> Link: http://lkml.kernel.org/r/1519352533-15992-2-git-send-email-ashok.raj@intel.com Link: https://lkml.kernel.org/r/20180228102846.13447-3-bp@alien8.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-12x86/microcode: Get rid of struct apply_microcode_ctxBorislav Petkov
commit 854857f5944c59a881ff607b37ed9ed41d031a3b upstream. It is a useless remnant from earlier times. Use the ucode_state enum directly. No functional change. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Ashok Raj <ashok.raj@intel.com> Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com> Link: https://lkml.kernel.org/r/20180228102846.13447-2-bp@alien8.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-12x86/CPU: Add a microcode loader callbackBorislav Petkov
commit 1008c52c09dcb23d93f8e0ea83a6246265d2cce0 upstream. Add a callback function which the microcode loader calls when microcode has been updated to a newer revision. Do the callback only when no error was encountered during loading. Tested-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Ashok Raj <ashok.raj@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20180216112640.11554-3-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-12x86/microcode: Propagate return value from updating functionsBorislav Petkov
commit 3f1f576a195aa266813cbd4ca70291deb61e0129 upstream. ... so that callers can know when microcode was updated and act accordingly. Tested-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Ashok Raj <ashok.raj@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20180216112640.11554-2-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-22x86/cpu: Change type of x86_cache_size variable to unsigned intGustavo A. R. Silva
commit 24dbc6000f4b9b0ef5a9daecb161f1907733765a upstream. Currently, x86_cache_size is of type int, which makes no sense as we will never have a valid cache size equal or less than 0. So instead of initializing this variable to -1, it can perfectly be initialized to 0 and use it as an unsigned variable instead. Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Addresses-Coverity-ID: 1464429 Link: http://lkml.kernel.org/r/20180213192208.GA26414@embeddedor.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-22x86/cpu: Rename cpu_data.x86_mask to cpu_data.x86_steppingJia Zhang
commit b399151cb48db30ad1e0e93dd40d68c6d007b637 upstream. x86_mask is a confusing name which is hard to associate with the processor's stepping. Additionally, correct an indent issue in lib/cpu.c. Signed-off-by: Jia Zhang <qianyue.zj@alibaba-inc.com> [ Updated it to more recent kernels. ] Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bp@alien8.de Cc: tony.luck@intel.com Link: http://lkml.kernel.org/r/1514771530-70829-1-git-send-email-qianyue.zj@alibaba-inc.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-24x86/microcode: Fix again accessing initrd after having been freedBorislav Petkov
Commit 24c2503255d3 ("x86/microcode: Do not access the initrd after it has been freed") fixed attempts to access initrd from the microcode loader after it has been freed. However, a similar KASAN warning was reported (stack trace edited): smpboot: Booting Node 0 Processor 1 APIC 0x11 ================================================================== BUG: KASAN: use-after-free in find_cpio_data+0x9b5/0xa50 Read of size 1 at addr ffff880035ffd000 by task swapper/1/0 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.14.8-slack #7 Hardware name: System manufacturer System Product Name/A88X-PLUS, BIOS 3003 03/10/2016 Call Trace: dump_stack print_address_description kasan_report ? find_cpio_data __asan_report_load1_noabort find_cpio_data find_microcode_in_initrd __load_ucode_amd load_ucode_amd_ap load_ucode_ap After some investigation, it turned out that a merge was done using the wrong side to resolve, leading to picking up the previous state, before the 24c2503255d3 fix. Therefore the Fixes tag below contains a merge commit. Revert the mismerge by catching the save_microcode_in_initrd_amd() retval and thus letting the function exit with the last return statement so that initrd_gone can be set to true. Fixes: f26483eaedec ("Merge branch 'x86/urgent' into x86/microcode, to resolve conflicts") Reported-by: <higuita@gmx.net> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://bugzilla.kernel.org/show_bug.cgi?id=198295 Link: https://lkml.kernel.org/r/20180123104133.918-2-bp@alien8.de
2018-01-24x86/microcode/intel: Extend BDW late-loading further with LLC size checkJia Zhang
Commit b94b73733171 ("x86/microcode/intel: Extend BDW late-loading with a revision check") reduced the impact of erratum BDF90 for Broadwell model 79. The impact can be reduced further by checking the size of the last level cache portion per core. Tony: "The erratum says the problem only occurs on the large-cache SKUs. So we only need to avoid the update if we are on a big cache SKU that is also running old microcode." For more details, see erratum BDF90 in document #334165 (Intel Xeon Processor E7-8800/4800 v4 Product Family Specification Update) from September 2017. Fixes: b94b73733171 ("x86/microcode/intel: Extend BDW late-loading with a revision check") Signed-off-by: Jia Zhang <zhang.jia@linux.alibaba.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Tony Luck <tony.luck@intel.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1516321542-31161-1-git-send-email-zhang.jia@linux.alibaba.com
2018-01-06x86/microcode/intel: Extend BDW late-loading with a revision checkJia Zhang
Instead of blacklisting all model 79 CPUs when attempting a late microcode loading, limit that only to CPUs with microcode revisions < 0x0b000021 because only on those late loading may cause a system hang. For such processors either: a) a BIOS update which might contain a newer microcode revision or b) the early microcode loading method should be considered. Processors with revisions 0x0b000021 or higher will not experience such hangs. For more details, see erratum BDF90 in document #334165 (Intel Xeon Processor E7-8800/4800 v4 Product Family Specification Update) from September 2017. [ bp: Heavily massage commit message and pr_* statements. ] Fixes: 723f2828a98c ("x86/microcode/intel: Disable late loading on model 79") Signed-off-by: Jia Zhang <qianyue.zj@alibaba-inc.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Tony Luck <tony.luck@intel.com> Cc: x86-ml <x86@kernel.org> Cc: <stable@vger.kernel.org> # v4.14 Link: http://lkml.kernel.org/r/1514772287-92959-1-git-send-email-qianyue.zj@alibaba-inc.com
2017-12-23Merge branch 'x86-pti-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 PTI preparatory patches from Thomas Gleixner: "Todays Advent calendar window contains twentyfour easy to digest patches. The original plan was to have twenty three matching the date, but a late fixup made that moot. - Move the cpu_entry_area mapping out of the fixmap into a separate address space. That's necessary because the fixmap becomes too big with NRCPUS=8192 and this caused already subtle and hard to diagnose failures. The top most patch is fresh from today and cures a brain slip of that tall grumpy german greybeard, who ignored the intricacies of 32bit wraparounds. - Limit the number of CPUs on 32bit to 64. That's insane big already, but at least it's small enough to prevent address space issues with the cpu_entry_area map, which have been observed and debugged with the fixmap code - A few TLB flush fixes in various places plus documentation which of the TLB functions should be used for what. - Rename the SYSENTER stack to CPU_ENTRY_AREA stack as it is used for more than sysenter now and keeping the name makes backtraces confusing. - Prevent LDT inheritance on exec() by moving it to arch_dup_mmap(), which is only invoked on fork(). - Make vysycall more robust. - A few fixes and cleanups of the debug_pagetables code. Check PAGE_PRESENT instead of checking the PTE for 0 and a cleanup of the C89 initialization of the address hint array which already was out of sync with the index enums. - Move the ESPFIX init to a different place to prepare for PTI. - Several code moves with no functional change to make PTI integration simpler and header files less convoluted. - Documentation fixes and clarifications" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits) x86/cpu_entry_area: Prevent wraparound in setup_cpu_entry_area_ptes() on 32bit init: Invoke init_espfix_bsp() from mm_init() x86/cpu_entry_area: Move it out of the fixmap x86/cpu_entry_area: Move it to a separate unit x86/mm: Create asm/invpcid.h x86/mm: Put MMU to hardware ASID translation in one place x86/mm: Remove hard-coded ASID limit checks x86/mm: Move the CR3 construction functions to tlbflush.h x86/mm: Add comments to clarify which TLB-flush functions are supposed to flush what x86/mm: Remove superfluous barriers x86/mm: Use __flush_tlb_one() for kernel memory x86/microcode: Dont abuse the TLB-flush interface x86/uv: Use the right TLB-flush API x86/entry: Rename SYSENTER_stack to CPU_ENTRY_AREA_entry_stack x86/doc: Remove obvious weirdnesses from the x86 MM layout documentation x86/mm/64: Improve the memory map documentation x86/ldt: Prevent LDT inheritance on exec x86/ldt: Rework locking arch, mm: Allow arch_dup_mmap() to fail x86/vsyscall/64: Warn and fail vsyscall emulation in NATIVE mode ...
2017-12-22x86/microcode: Dont abuse the TLB-flush interfacePeter Zijlstra
Commit: ec400ddeff20 ("x86/microcode_intel_early.c: Early update ucode on Intel's CPU") ... grubbed into tlbflush internals without coherent explanation. Since it says its a precaution and the SDM doesn't mention anything like this, take it out back. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Laight <David.Laight@aculab.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Eduardo Valentin <eduval@amazon.com> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will.deacon@arm.com> Cc: aliguori@amazon.com Cc: daniel.gruss@iaik.tugraz.at Cc: fenghua.yu@intel.com Cc: hughd@google.com Cc: keescook@google.com Cc: linux-mm@kvack.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-06x86/microcode/AMD: Add support for fam17h microcode loadingTom Lendacky
The size for the Microcode Patch Block (MPB) for an AMD family 17h processor is 3200 bytes. Add a #define for fam17h so that it does not default to 2048 bytes and fail a microcode load/update. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@alien8.de> Link: https://lkml.kernel.org/r/20171130224640.15391.40247.stgit@tlendack-t1.amdoffice.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-18x86/microcode/intel: Disable late loading on model 79Borislav Petkov
Blacklist Broadwell X model 79 for late loading due to an erratum. Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Tony Luck <tony.luck@intel.com> Cc: <stable@vger.kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20171018111225.25635-1-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-14x86/microcode: Do the family check firstBorislav Petkov
On CPUs like AMD's Geode, for example, we shouldn't even try to load microcode because they do not support the modern microcode loading interface. However, we do the family check *after* the other checks whether the loader has been disabled on the command line or whether we're running in a guest. So move the family checks first in order to exit early if we're being loaded on an unsupported family. Reported-and-tested-by: Sven Glodowski <glodi1@arcor.de> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: <stable@vger.kernel.org> # 4.11.. Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://bugzilla.suse.com/show_bug.cgi?id=1061396 Link: http://lkml.kernel.org/r/20171012112316.977-1-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-04Merge branch 'x86-microcode-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 microcode loading updates from Ingo Molnar: "Update documentation, improve robustness and fix a memory leak" * 'x86-microcode-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/microcode/intel: Improve microcode patches saving flow x86/microcode: Document the three loading methods x86/microcode/AMD: Free unneeded patch before exit from update_cache()
2017-08-29x86/microcode/intel: Improve microcode patches saving flowBorislav Petkov
Avoid potentially dereferencing a NULL pointer when saving a microcode patch for early loading on the application processors. While at it, drop the IS_ERR() checking in favor of simpler, NULL-ptr checks which are sufficient and rename __alloc_microcode_buf() to memdup_patch() to more precisely denote what it does. No functionality change. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: kernel-janitors@vger.kernel.org Link: http://lkml.kernel.org/r/20170825100456.n236w3jebteokfd6@pd.tnic
2017-08-18x86: Constify attribute_group structuresArvind Yadav
attribute_groups are not supposed to change at runtime and none of the groups is modified. Mark the non-const structs as const. [ tglx: Folded into one big patch ] Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: tony.luck@intel.com Cc: bp@alien8.de Link: http://lkml.kernel.org/r/1500550238-15655-2-git-send-email-arvind.yadav.cs@gmail.com
2017-07-25x86/microcode/AMD: Free unneeded patch before exit from update_cache()Shu Wang
verify_and_add_patch() allocates memory for a microcode patch and hands it down to be added to the cache of patches. However, if the cache already has the latest patch, the newly allocated one needs to be freed before returning. Do that. This issue has been found by kmemleak: unreferenced object 0xffff88010e780b40 (size 32): comm "bash", pid 860, jiffies 4294690939 (age 29.297s) backtrace: kmemleak_alloc kmem_cache_alloc_trace load_microcode_amd.isra.0 request_microcode_amd reload_store dev_attr_store sysfs_kf_write kernfs_fop_write __vfs_write vfs_write SyS_write do_syscall_64 return_from_SYSCALL_64 0xffffffffffffffff (gdb) list *0xffffffff81050d60 0xffffffff81050d60 is in load_microcode_amd (arch/x86/kernel/cpu/microcode/amd.c:616). which is this: patch = kzalloc(sizeof(*patch), GFP_KERNEL); --> if (!patch) { pr_err("Patch allocation failure.\n"); return -EINVAL; } Signed-off-by: Shu Wang <shuwang@redhat.com> [ Rewrite commit message. ] Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: chuhu@redhat.com Cc: liwang@redhat.com Link: http://lkml.kernel.org/r/20170724101228.17326-2-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-26x86/microcode: Make a couple of symbols staticColin Ian King
The helper function __load_ucode_amd() and pointer intel_ucode_patch do not need to be in global scope, so make them static. Fixes those sparse warnings: "symbol '__load_ucode_amd' was not declared. Should it be static?" "symbol 'intel_ucode_patch' was not declared. Should it be static?" Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170622095736.11937-1-colin.king@canonical.com
2017-06-20x86/microcode/intel: Save pointer to ucode patch for early AP loadingBorislav Petkov
Normally, when the initrd is gone, we can't search it for microcode blobs to apply anymore. For that we need to stash away the patch in our own storage. And save_microcode_in_initrd_intel() looks like the proper place to do that from. So in order for early loading to work, invalidate the intel_ucode_patch pointer to the patch *before* scanning the initrd one last time. If the scanning code finds a microcode patch, it will assign that pointer again, this time with our own storage's address. This way, early microcode application during resume-from-RAM works too, even after the initrd is long gone. Tested-by: Dominik Brodowski <linux@dominikbrodowski.net> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170614140626.4462-2-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-20x86/microcode: Look for the initrd at the correct address on 32-bitBorislav Petkov
Early during boot, the BSP finds the ramdisk's position from boot_params but by the time the APs get to boot, the BSP has continued in the mean time and has potentially managed to relocate that ramdisk. And in that case, the APs need to find the ramdisk at its new position, in *physical* memory as they're running before paging has been enabled. Thus, get the updated physical location of the ramdisk which is in the relocated_ramdisk variable. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170614140626.4462-1-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-08x86/microcode/intel: Clear patch pointer before jettisoning the initrdDominik Brodowski
During early boot, load_ucode_intel_ap() uses __load_ucode_intel() to obtain a pointer to the relevant microcode patch (embedded in the initrd), and stores this value in 'intel_ucode_patch' to speed up the microcode patch application for subsequent CPUs. On resuming from suspend-to-RAM, however, load_ucode_ap() calls load_ucode_intel_ap() for each non-boot-CPU. By then the initramfs is long gone so the pointer stored in 'intel_ucode_patch' no longer points to a valid microcode patch. Clear that pointer so that we effectively fall back to the CPU hotplug notifier callbacks to update the microcode. Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> [ Edit and massage commit message. ] Signed-off-by: Borislav Petkov <bp@suse.de> Cc: <stable@vger.kernel.org> # 4.10.. Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170607095819.9754-1-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-29x86/microcode/AMD: Change load_microcode_amd()'s param to bool to fix ↵Borislav Petkov
preemptibility bug With CONFIG_DEBUG_PREEMPT enabled, I get: BUG: using smp_processor_id() in preemptible [00000000] code: swapper/0/1 caller is debug_smp_processor_id CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.12.0-rc2+ #2 Call Trace: dump_stack check_preemption_disabled debug_smp_processor_id save_microcode_in_initrd_amd ? microcode_init save_microcode_in_initrd ... because, well, it says it above, we're using smp_processor_id() in preemptible code. But passing the CPU number is not really needed. It is only used to determine whether we're on the BSP, and, if so, to save the microcode patch for early loading. [ We don't absolutely need to do it on the BSP but we do that customarily there. ] Instead, convert that function parameter to a boolean which denotes whether the patch should be saved or not, thereby avoiding the use of smp_processor_id() in preemptible code. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170528200414.31305-1-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-12Tigran has movedAndrew Morton
Cc: Tigran Aivazian <aivazian.tigran@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-03-18x86/microcode/AMD: Remove redundant NULL check on mcColin Ian King
mc is a pointer to the static u8 array amd_ucode_patch and therefore can never be null, so the check is redundant. Remove it. Detected by CoverityScan, CID#1372871 ("Logically Dead Code") Signed-off-by: Colin Ian King <colin.king@canonical.com> Cc: kernel-janitors@vger.kernel.org Cc: x86-ml <x86@kernel.org> Link: http://lkml.kernel.org/r/20170315171010.17536-1-colin.king@canonical.com Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-01-31Merge branch 'x86/urgent' into x86/microcode, to resolve conflictsIngo Molnar
Conflicts: arch/x86/kernel/cpu/microcode/amd.c arch/x86/kernel/cpu/microcode/core.c Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-30x86/microcode: Do not access the initrd after it has been freedBorislav Petkov
When we look for microcode blobs, we first try builtin and if that doesn't succeed, we fallback to the initrd supplied to the kernel. However, at some point doing boot, that initrd gets jettisoned and we shouldn't access it anymore. But we do, as the below KASAN report shows. That's because find_microcode_in_initrd() doesn't check whether the initrd is still valid or not. So do that. ================================================================== BUG: KASAN: use-after-free in find_cpio_data Read of size 1 by task swapper/1/0 page:ffffea0000db9d40 count:0 mapcount:0 mapping: (null) index:0x1 flags: 0x100000000000000() raw: 0100000000000000 0000000000000000 0000000000000001 00000000ffffffff raw: dead000000000100 dead000000000200 0000000000000000 0000000000000000 page dumped because: kasan: bad access detected CPU: 1 PID: 0 Comm: swapper/1 Tainted: G W 4.10.0-rc5-debug-00075-g2dbde22 #3 Hardware name: Dell Inc. XPS 13 9360/0839Y6, BIOS 1.2.3 12/01/2016 Call Trace: dump_stack ? _atomic_dec_and_lock ? __dump_page kasan_report_error ? pointer ? find_cpio_data __asan_report_load1_noabort ? find_cpio_data find_cpio_data ? vsprintf ? dump_stack ? get_ucode_user ? print_usage_bug find_microcode_in_initrd __load_ucode_intel ? collect_cpu_info_early ? debug_check_no_locks_freed load_ucode_intel_ap ? collect_cpu_info ? trace_hardirqs_on ? flat_send_IPI_mask_allbutself load_ucode_ap ? get_builtin_firmware ? flush_tlb_func ? do_raw_spin_trylock ? cpumask_weight cpu_init ? trace_hardirqs_off ? play_dead_common ? native_play_dead ? hlt_play_dead ? syscall_init ? arch_cpu_idle_dead ? do_idle start_secondary start_cpu Memory state around the buggy address: ffff880036e74f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff880036e74f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff880036e75000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff880036e75080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff880036e75100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== Reported-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Tested-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170126165833.evjemhbqzaepirxo@pd.tnic Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-23x86/microcode/AMD: Remove struct cont_desc.eq_idBorislav Petkov
The equivalence ID was needed outside of the container scanning logic but now, after this has been cleaned up, not anymore. Now, cont_desc.mc is used to denote whether the container we're looking at has the proper microcode patch for this CPU or not. Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/20170120202955.4091-17-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-01-23x86/microcode/AMD: Remove AP scanning optimizationBorislav Petkov
The idea was to not scan the microcode blob on each AP (Application Processor) during boot and thus save us some milliseconds. However, on architectures where the microcode engine is shared between threads, this doesn't work. Here's why: The microcode on CPU0, i.e., the first thread, gets updated. The second thread, i.e., CPU1, i.e., the first AP walks into load_ucode_amd_ap(), sees that there's no container cached and goes and scans for the proper blob. It finds it and as a last step of apply_microcode_early_amd(), it tries to apply the patch but that core has already the updated microcode revision which it has received through CPU0's update. So it returns false and we do desc->size = -1 to prevent other APs from scanning. However, the next AP, CPU2, has a different microcode engine which hasn't been updated yet. The desc->size == -1 test prevents it from scanning the blob anew and we fail to update it. The fix is much more straight-forward than it looks: the BSP (BootStrapping Processor), i.e., CPU0, caches the microcode patch in amd_ucode_patch. We use that on the AP and try to apply it. In the 99.9999% of cases where we have homogeneous cores - *not* mixed-steppings - the application will be successful and we're good to go. In the remaining small set of systems, we will simply rescan the blob and find (or not, if none present) the proper patch and apply it then. Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170120202955.4091-16-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-01-23x86/microcode/AMD: Simplify saving from initrdBorislav Petkov
No need to use the previously stashed info in the container - simply go ahead and parse the initrd once more. It simplifies and streamlines the code a whole lot. Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170120202955.4091-15-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-01-23x86/microcode/AMD: Unify load_ucode_amd_ap()Borislav Petkov
Use a version for both bitness by adding a helper which does the actual container finding and parsing which can be used on any CPU - BSP or AP. Streamlines the paths more. Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/20170120202955.4091-14-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-01-23x86/microcode/AMD: Check patch level only on the BSPBorislav Petkov
Check final patch levels for AMD only on the BSP. This way, we decide early and only once whether to continue loading or to leave the loader disabled on such systems. Simplify a lot. Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/20170120202955.4091-13-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-01-23x86/microcode: Remove local vendor variableBorislav Petkov
Use x86_cpuid_vendor() directly. No functionality change. Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/20170120202955.4091-12-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-01-23x86/microcode/AMD: Use find_microcode_in_initrd()Borislav Petkov
Use the generic helper instead of semi-open-coding the procedure. Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170120202955.4091-11-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-01-23x86/microcode/AMD: Get rid of global this_equiv_idBorislav Petkov
We have a container which we update/prepare each time before applying a microcode patch instead of using a global. Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170120202955.4091-10-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-01-23x86/microcode: Decrease CPUID useBorislav Petkov
Get CPUID(1).EAX value once per CPU and propagate value into the callers instead of conveniently calling it every time. Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170120202955.4091-9-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-01-23x86/microcode/AMD: Rework container parsingBorislav Petkov
It was pretty clumsy before and the whole work of parsing the microcode containers was spread around the functions wrongly. Clean it up so that there's a main scan_containers() function which iterates over the microcode blob and picks apart the containers glued together. For each container, it calls a parse_container() helper which concentrates on one container only: sanity-checking, parsing, counting microcode patches in there, etc. It makes much more sense now and it is actually very readable. Oh, and we luvz a diffstat removing more crap than adding. Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/20170120202955.4091-8-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-01-23x86/microcode/AMD: Extend the container structBorislav Petkov
Make it into a container descriptor which is being passed around and stores important info like the matching container and the patch for the current CPU. Make it static too. Later patches will use this and thus get rid of a double container parsing. Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170120202955.4091-7-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-01-23x86/microcode/AMD: Shorten function parameter's nameBorislav Petkov
The whole driver calls this "mc", do that here too. No functionality change. Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170120202955.4091-6-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-01-23x86/microcode/AMD: Clean up find_equiv_id()Borislav Petkov
No need to have it marked "inline" - let gcc decide. Also, shorten the argument name and simplify while-test. While at it, make it into a proper for-loop and simplify it even more, as tglx suggests. No functionality change. Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/20170120202955.4091-5-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-01-23x86/microcode/intel: Drop stashed AP patch pointer optimizationBorislav Petkov
This was meant to save us the scanning of the microcode containter in the initrd since the first AP had already done that but it can also hurt us: Imagine a single hyperthreaded CPU (Intel(R) Atom(TM) CPU N270, for example) which updates the microcode on the BSP but since the microcode engine is shared between the two threads, the update on CPU1 doesn't happen because it has already happened on CPU0 and we don't find a newer microcode revision on CPU1. Which doesn't set the intel_ucode_patch pointer and at initrd jettisoning time we don't save the microcode patch for later application. Now, when we suspend to RAM, the loaded microcode gets cleared so we need to reload but there's no patch saved in the cache. Removing the optimization fixes this issue and all is fine and dandy. Fixes: 06b8534cb728 ("x86/microcode: Rework microcode loading") Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170120202955.4091-2-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-01-09x86/microcode/intel: Use correct buffer size for saving microcode dataJunichi Nomura
In generic_load_microcode(), curr_mc_size is the size of the last allocated buffer and since we have this performance "optimization" there to vmalloc a new buffer only when the current one is bigger, curr_mc_size ends up becoming the size of the biggest buffer we've seen so far. However, we end up saving the microcode patch which matches our CPU and its size is not curr_mc_size but the respective mc_size during the iteration while we're staring at it. So save that mc_size into a separate variable and use it to store the previously found microcode buffer. Without this fix, we could get oops like this: BUG: unable to handle kernel paging request at ffffc9000e30f000 IP: __memcpy+0x12/0x20 ... Call Trace: ? kmemdup+0x43/0x60 __alloc_microcode_buf+0x44/0x70 save_microcode_patch+0xd4/0x150 generic_load_microcode+0x1b8/0x260 request_microcode_user+0x15/0x20 microcode_write+0x91/0x100 __vfs_write+0x34/0x120 vfs_write+0xc1/0x130 SyS_write+0x56/0xc0 do_syscall_64+0x6c/0x160 entry_SYSCALL64_slow_path+0x25/0x25 Fixes: 06b8534cb728 ("x86/microcode: Rework microcode loading") Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/4f33cbfd-44f2-9bed-3b66-7446cd14256f@ce.jp.nec.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-01-09x86/microcode/intel: Fix allocation size of struct ucode_patchJunichi Nomura
We allocate struct ucode_patch here. @size is the size of microcode data and used for kmemdup() later in this function. Fixes: 06b8534cb728 ("x86/microcode: Rework microcode loading") Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/7a730dc9-ac17-35c4-fe76-dfc94e5ecd95@ce.jp.nec.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>