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2025-03-10x86/microcode/AMD: Fix out-of-bounds on systems with CPU-less NUMA nodesFlorent Revest
Currently, load_microcode_amd() iterates over all NUMA nodes, retrieves their CPU masks and unconditionally accesses per-CPU data for the first CPU of each mask. According to Documentation/admin-guide/mm/numaperf.rst: "Some memory may share the same node as a CPU, and others are provided as memory only nodes." Therefore, some node CPU masks may be empty and wouldn't have a "first CPU". On a machine with far memory (and therefore CPU-less NUMA nodes): - cpumask_of_node(nid) is 0 - cpumask_first(0) is CONFIG_NR_CPUS - cpu_data(CONFIG_NR_CPUS) accesses the cpu_info per-CPU array at an index that is 1 out of bounds This does not have any security implications since flashing microcode is a privileged operation but I believe this has reliability implications by potentially corrupting memory while flashing a microcode update. When booting with CONFIG_UBSAN_BOUNDS=y on an AMD machine that flashes a microcode update. I get the following splat: UBSAN: array-index-out-of-bounds in arch/x86/kernel/cpu/microcode/amd.c:X:Y index 512 is out of range for type 'unsigned long[512]' [...] Call Trace: dump_stack __ubsan_handle_out_of_bounds load_microcode_amd request_microcode_amd reload_store kernfs_fop_write_iter vfs_write ksys_write do_syscall_64 entry_SYSCALL_64_after_hwframe Change the loop to go over only NUMA nodes which have CPUs before determining whether the first CPU on the respective node needs microcode update. [ bp: Massage commit message, fix typo. ] Fixes: 7ff6edf4fef3 ("x86/microcode/AMD: Fix mixed steppings support") Signed-off-by: Florent Revest <revest@chromium.org> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20250310144243.861978-1-revest@chromium.org
2025-03-08x86/microcode/AMD: Add some forgotten models to the SHA checkBorislav Petkov (AMD)
Add some more forgotten models to the SHA check. Fixes: 50cef76d5cb0 ("x86/microcode/AMD: Load only SHA256-checksummed patches") Reported-by: Toralf Förster <toralf.foerster@gmx.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Tested-by: Toralf Förster <toralf.foerster@gmx.de> Link: https://lore.kernel.org/r/20250307220256.11816-1-bp@kernel.org
2025-02-22x86/microcode/AMD: Load only SHA256-checksummed patchesBorislav Petkov (AMD)
Load patches for which the driver carries a SHA256 checksum of the patch blob. This can be disabled by adding "microcode.amd_sha_check=off" on the kernel cmdline. But it is highly NOT recommended. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2025-02-17x86/microcode/AMD: Add get_patch_level()Borislav Petkov (AMD)
Put the MSR_AMD64_PATCH_LEVEL reading of the current microcode revision the hw has, into a separate function. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20250211163648.30531-6-bp@kernel.org
2025-02-17x86/microcode/AMD: Get rid of the _load_microcode_amd() forward declarationBorislav Petkov (AMD)
Simply move save_microcode_in_initrd() down. No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20250211163648.30531-5-bp@kernel.org
2025-02-17x86/microcode/AMD: Merge early_apply_microcode() into its single callsiteBorislav Petkov (AMD)
No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20250211163648.30531-4-bp@kernel.org
2025-02-17x86/microcode/AMD: Remove unused save_microcode_in_initrd_amd() declarationsBorislav Petkov (AMD)
Commit a7939f016720 ("x86/microcode/amd: Cache builtin/initrd microcode early") renamed it to save_microcode_in_initrd() and made it static. Zap the forgotten declarations. No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20250211163648.30531-3-bp@kernel.org
2025-02-17x86/microcode/AMD: Remove ugly linebreak in __verify_patch_section() signatureBorislav Petkov (AMD)
No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20250211163648.30531-2-bp@kernel.org
2024-12-31x86/microcode/AMD: Remove ret local var in early_apply_microcode()Borislav Petkov (AMD)
No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2024-12-31x86/microcode/AMD: Have __apply_microcode_amd() return boolBorislav Petkov (AMD)
This is the natural thing to do anyway. No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2024-12-31x86/microcode/AMD: Make __verify_patch_size() return boolNikolay Borisov
The result of that function is in essence boolean, so simplify to return the result of the relevant expression. It also makes it follow the convention used by __verify_patch_section(). No functional changes. Signed-off-by: Nikolay Borisov <nik.borisov@suse.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20241018155151.702350-3-nik.borisov@suse.com
2024-12-31x86/microcode/AMD: Remove bogus comment from parse_container()Nikolay Borisov
The function doesn't return an equivalence ID, remove the false comment. Signed-off-by: Nikolay Borisov <nik.borisov@suse.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20241018155151.702350-4-nik.borisov@suse.com
2024-12-31x86/microcode/AMD: Return bool from find_blobs_in_containers()Nikolay Borisov
Instead of open-coding the check for size/data move it inside the function and make it return a boolean indicating whether data was found or not. No functional changes. [ bp: Write @ret in find_blobs_in_containers() only on success. ] Signed-off-by: Nikolay Borisov <nik.borisov@suse.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20241018155151.702350-2-nik.borisov@suse.com
2024-11-25x86/microcode/AMD: Flush patch buffer mapping after applicationBorislav Petkov (AMD)
Due to specific requirements while applying microcode patches on Zen1 and 2, the patch buffer mapping needs to be flushed from the TLB after application. Do so. If not, unnecessary and unnatural delays happen in the boot process. Reported-by: Thomas De Schampheleire <thomas.de_schampheleire@nokia.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Thomas De Schampheleire <thomas.de_schampheleire@nokia.com> Cc: <stable@kernel.org> # f1d84b59cbb9 ("x86/mm: Carve out INVLPG inline asm for use by others") Link: https://lore.kernel.org/r/ZyulbYuvrkshfsd2@antipodes
2024-10-22x86/microcode/AMD: Split load_microcode_amd()Borislav Petkov (AMD)
This function should've been split a long time ago because it is used in two paths: 1) On the late loading path, when the microcode is loaded through the request_firmware interface 2) In the save_microcode_in_initrd() path which collects all the microcode patches which are relevant for the current system before the initrd with the microcode container has been jettisoned. In that path, it is not really necessary to iterate over the nodes on a system and match a patch however it didn't cause any trouble so it was left for a later cleanup However, that later cleanup was expedited by the fact that Jens was enabling "Use L3 as a NUMA node" in the BIOS setting in his machine and so this causes the NUMA CPU masks used in cpumask_of_node() to be generated *after* 2) above happened on the first node. Which means, all those masks were funky, wrong, uninitialized and whatnot, leading to explosions when dereffing c->microcode in load_microcode_amd(). So split that function and do only the necessary work needed at each stage. Fixes: 94838d230a6c ("x86/microcode/AMD: Use the family,model,stepping encoded in the patch ID") Reported-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Jens Axboe <axboe@kernel.dk> Link: https://lore.kernel.org/r/91194406-3fdf-4e38-9838-d334af538f74@kernel.dk
2024-10-22x86/microcode/AMD: Pay attention to the stepping dynamicallyBorislav Petkov (AMD)
Commit in Fixes changed how a microcode patch is loaded on Zen and newer but the patch matching needs to happen with different rigidity, depending on what is being done: 1) When the patch is added to the patches cache, the stepping must be ignored because the driver still supports different steppings per system 2) When the patch is matched for loading, then the stepping must be taken into account because each CPU needs the patch matching its exact stepping Take care of that by making the matching smarter. Fixes: 94838d230a6c ("x86/microcode/AMD: Use the family,model,stepping encoded in the patch ID") Reported-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Jens Axboe <axboe@kernel.dk> Link: https://lore.kernel.org/r/91194406-3fdf-4e38-9838-d334af538f74@kernel.dk
2024-07-30x86/microcode/AMD: Fix a -Wsometimes-uninitialized clang false positiveBorislav Petkov (AMD)
Initialize equiv_id in order to shut up: arch/x86/kernel/cpu/microcode/amd.c:714:6: warning: variable 'equiv_id' is \ used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized] if (x86_family(bsp_cpuid_1_eax) < 0x17) { ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ because clang doesn't do interprocedural analysis for warnings to see that this variable won't be used uninitialized. Fixes: 94838d230a6c ("x86/microcode/AMD: Use the family,model,stepping encoded in the patch ID") Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202407291815.gJBST0P3-lkp@intel.com/ Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2024-07-29x86/microcode/AMD: Use the family,model,stepping encoded in the patch IDBorislav Petkov
On Zen and newer, the family, model and stepping is part of the microcode patch ID so that the equivalence table the driver has been using, is not needed anymore. So switch the driver to use that from now on. The equivalence table in the microcode blob should still remain in case there's need to pass some additional information to the kernel loader. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20240725112037.GBZqI1BbUk1KMlOJ_D@fat_crate.local
2024-04-05x86/microcode/AMD: Remove unused PATCH_MAX_SIZE macroBorislav Petkov (AMD)
Orphaned after 05e91e721138 ("x86/microcode/AMD: Rip out static buffers") No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2024-04-05x86/microcode/AMD: Avoid -Wformat warning with clang-15Arnd Bergmann
Older versions of clang show a warning for amd.c after a fix for a gcc warning: arch/x86/kernel/cpu/microcode/amd.c:478:47: error: format specifies type \ 'unsigned char' but the argument has type 'u16' (aka 'unsigned short') [-Werror,-Wformat] "amd-ucode/microcode_amd_fam%02hhxh.bin", family); ~~~~~~ ^~~~~~ %02hx In clang-16 and higher, this warning is disabled by default, but clang-15 is still supported, and it's trivial to avoid by adapting the types according to the range of the passed data and the format string. [ bp: Massage commit message. ] Fixes: 2e9064faccd1 ("x86/microcode/amd: Fix snprintf() format string warning in W=1 build") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20240405204919.1003409-1-arnd@kernel.org
2023-11-21x86/microcode: Rework early revisions reportingBorislav Petkov (AMD)
The AMD side of the loader issues the microcode revision for each logical thread on the system, which can become really noisy on huge machines. And doing that doesn't make a whole lot of sense - the microcode revision is already in /proc/cpuinfo. So in case one is interested in the theoretical support of mixed silicon steppings on AMD, one can check there. What is also missing on the AMD side - something which people have requested before - is showing the microcode revision the CPU had *before* the early update. So abstract that up in the main code and have the BSP on each vendor provide those revision numbers. Then, dump them only once on driver init. On Intel, do not dump the patch date - it is not needed. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/CAHk-=wg=%2B8rceshMkB4VnKxmRccVLtBLPBawnewZuuqyx5U=3A@mail.gmail.com
2023-10-24x86/microcode: Prepare for minimal revision checkThomas Gleixner
Applying microcode late can be fatal for the running kernel when the update changes functionality which is in use already in a non-compatible way, e.g. by removing a CPUID bit. There is no way for admins which do not have access to the vendors deep technical support to decide whether late loading of such a microcode is safe or not. Intel has added a new field to the microcode header which tells the minimal microcode revision which is required to be active in the CPU in order to be safe. Provide infrastructure for handling this in the core code and a command line switch which allows to enforce it. If the update is considered safe the kernel is not tainted and the annoying warning message not emitted. If it's enforced and the currently loaded microcode revision is not safe for late loading then the load is aborted. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20231017211724.079611170@linutronix.de
2023-10-24x86/microcode: Handle "nosmt" correctlyThomas Gleixner
On CPUs where microcode loading is not NMI-safe the SMT siblings which are parked in one of the play_dead() variants still react to NMIs. So if an NMI hits while the primary thread updates the microcode the resulting behaviour is undefined. The default play_dead() implementation on modern CPUs is using MWAIT which is not guaranteed to be safe against a microcode update which affects MWAIT. Take the cpus_booted_once_mask into account to detect this case and refuse to load late if the vendor specific driver does not advertise that late loading is NMI safe. AMD stated that this is safe, so mark the AMD driver accordingly. This requirement will be partially lifted in later changes. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20231002115903.087472735@linutronix.de
2023-10-24x86/microcode/amd: Use cached microcode for AP loadThomas Gleixner
Now that the microcode cache is initialized before the APs are brought up, there is no point in scanning builtin/initrd microcode during AP loading. Convert the AP loader to utilize the cache, which in turn makes the CPU hotplug callback which applies the microcode after initrd/builtin is gone, obsolete as the early loading during late hotplug operations including the resume path depends now only on the cache. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20231017211723.243426023@linutronix.de
2023-10-24x86/microcode/amd: Cache builtin/initrd microcode earlyThomas Gleixner
There is no reason to scan builtin/initrd microcode on each AP. Cache the builtin/initrd microcode in an early initcall so that the early AP loader can utilize the cache. The existing fs initcall which invoked save_microcode_in_initrd_amd() is still required to maintain the initrd_gone flag. Rename it accordingly. This will be removed once the AP loader code is converted to use the cache. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20231017211723.187566507@linutronix.de
2023-10-24x86/microcode/amd: Cache builtin microcode tooThomas Gleixner
save_microcode_in_initrd_amd() fails to cache builtin microcode and only scans initrd. Use find_blobs_in_containers() instead which covers both. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20231010150702.495139089@linutronix.de
2023-10-24x86/microcode/amd: Use correct per CPU ucode_cpu_infoThomas Gleixner
find_blobs_in_containers() is invoked on every CPU but overwrites unconditionally ucode_cpu_info of CPU0. Fix this by using the proper CPU data and move the assignment into the call site apply_ucode_from_containers() so that the function can be reused. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20231010150702.433454320@linutronix.de
2023-10-19x86/microcode/intel: Rip out mixed stepping support for Intel CPUsAshok Raj
Mixed steppings aren't supported on Intel CPUs. Only one microcode patch is required for the entire system. The caching of microcode blobs which match the family and model is therefore pointless and in fact is dysfunctional as CPU hotplug updates use only a single microcode blob, i.e. the one where *intel_ucode_patch points to. Remove the microcode cache and make it an AMD local feature. [ tglx: - save only at the end. Otherwise random microcode ends up in the pointer for early loading - free the ucode patch pointer in save_microcode_patch() only after kmemdup() has succeeded, as reported by Andrew Cooper ] Originally-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20231017211722.404362809@linutronix.de
2023-10-18x86/microcode/32: Move early loading after paging enableThomas Gleixner
32-bit loads microcode before paging is enabled. The commit which introduced that has zero justification in the changelog. The cover letter has slightly more content, but it does not give any technical justification either: "The problem in current microcode loading method is that we load a microcode way, way too late; ideally we should load it before turning paging on. This may only be practical on 32 bits since we can't get to 64-bit mode without paging on, but we should still do it as early as at all possible." Handwaving word salad with zero technical content. Someone claimed in an offlist conversation that this is required for curing the ATOM erratum AAE44/AAF40/AAG38/AAH41. That erratum requires an microcode update in order to make the usage of PSE safe. But during early boot, PSE is completely irrelevant and it is evaluated way later. Neither is it relevant for the AP on single core HT enabled CPUs as the microcode loading on the AP is not doing anything. On dual core CPUs there is a theoretical problem if a split of an executable large page between enabling paging including PSE and loading the microcode happens. But that's only theoretical, it's practically irrelevant because the affected dual core CPUs are 64bit enabled and therefore have paging and PSE enabled before loading the microcode on the second core. So why would it work on 64-bit but not on 32-bit? The erratum: "AAG38 Code Fetch May Occur to Incorrect Address After a Large Page is Split Into 4-Kbyte Pages Problem: If software clears the PS (page size) bit in a present PDE (page directory entry), that will cause linear addresses mapped through this PDE to use 4-KByte pages instead of using a large page after old TLB entries are invalidated. Due to this erratum, if a code fetch uses this PDE before the TLB entry for the large page is invalidated then it may fetch from a different physical address than specified by either the old large page translation or the new 4-KByte page translation. This erratum may also cause speculative code fetches from incorrect addresses." The practical relevance for this is exactly zero because there is no splitting of large text pages during early boot-time, i.e. between paging enable and microcode loading, and neither during CPU hotplug. IOW, this load microcode before paging enable is yet another voodoo programming solution in search of a problem. What's worse is that it causes at least two serious problems: 1) When stackprotector is enabled, the microcode loader code has the stackprotector mechanics enabled. The read from the per CPU variable __stack_chk_guard is always accessing the virtual address either directly on UP or via %fs on SMP. In physical address mode this results in an access to memory above 3GB. So this works by chance as the hardware returns the same value when there is no RAM at this physical address. When there is RAM populated above 3G then the read is by chance the same as nothing changes that memory during the very early boot stage. That's not necessarily true during runtime CPU hotplug. 2) When function tracing is enabled, the relevant microcode loader functions and the functions invoked from there will call into the tracing code and evaluate global and per CPU variables in physical address mode. What could potentially go wrong? Cure this and move the microcode loading after the early paging enable, use the new temporary initrd mapping and remove the gunk in the microcode loader which is required to handle physical address mode. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20231017211722.348298216@linutronix.de
2023-10-17x86/microcode/amd: Fix snprintf() format string warning in W=1 buildPaolo Bonzini
Building with GCC 11.x results in the following warning: arch/x86/kernel/cpu/microcode/amd.c: In function ‘find_blobs_in_containers’: arch/x86/kernel/cpu/microcode/amd.c:504:58: error: ‘h.bin’ directive output may be truncated writing 5 bytes into a region of size between 1 and 7 [-Werror=format-truncation=] arch/x86/kernel/cpu/microcode/amd.c:503:17: note: ‘snprintf’ output between 35 and 41 bytes into a destination of size 36 The issue is that GCC does not know that the family can only be a byte (it ultimately comes from CPUID). Suggest the right size to the compiler by marking the argument as char-size ("hh"). While at it, instead of using the slightly more obscure precision specifier use the width with zero padding (over 23000 occurrences in kernel sources, vs 500 for the idiom using the precision). Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Closes: https://lore.kernel.org/oe-kbuild-all/202308252255.2HPJ6x5Q-lkp@intel.com/ Link: https://lore.kernel.org/r/20231016224858.2829248-1-pbonzini@redhat.com
2023-08-13x86/microcode: Move core specific defines to local headerThomas Gleixner
There is no reason to expose all of this globally. Move everything which is not required outside of the microcode specific code to local header files and into the respective source files. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20230812195727.952876381@linutronix.de
2023-08-13x86/microcode: Include vendor headers into microcode.hAshok Raj
Currently vendor specific headers are included explicitly when used in common code. Instead, include the vendor specific headers in microcode.h, and include that in all usages. No functional change. Suggested-by: Boris Petkov <bp@alien8.de> Signed-off-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20230812195727.776541545@linutronix.de
2023-07-27x86/microcode/AMD: Rip out static buffersBorislav Petkov (AMD)
Load straight from the containers (initrd or builtin, for example). There's no need to cache the patch per node. This even simplifies the code a bit with the opportunity for more cleanups later. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: John Allen <john.allen@amd.com> Link: https://lore.kernel.org/r/20230720202813.3269888-1-john.allen@amd.com
2023-06-12x86/microcode/AMD: Load late on both threads tooBorislav Petkov (AMD)
Do the same as early loading - load on both threads. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: <stable@kernel.org> Link: https://lore.kernel.org/r/20230605141332.25948-1-bp@alien8.de
2023-05-08x86/microcode/amd: Remove unneeded pointer arithmeticNathan Fontenot
Remove unneeded pointer increment arithmetic, the pointer is set at the beginning of the loop. Signed-off-by: Nathan Fontenot <nathan.fontenot@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20230502174232.73880-1-nathan.fontenot@amd.com
2023-05-08x86/microcode/AMD: Get rid of __find_equiv_id()Borislav Petkov (AMD)
Merge it into its only call site. No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20230227160352.7260-1-bp@alien8.de
2023-03-30docs: move x86 documentation into Documentation/arch/Jonathan Corbet
Move the x86 documentation under Documentation/arch/ as a way of cleaning up the top-level directory and making the structure of our docs more closely match the structure of the source directories it describes. All in-kernel references to the old paths have been updated. Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: linux-arch@vger.kernel.org Cc: x86@kernel.org Cc: Borislav Petkov <bp@alien8.de> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/lkml/20230315211523.108836-1-corbet@lwn.net/ Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-02-06x86/microcode/AMD: Fix mixed steppings supportBorislav Petkov (AMD)
The AMD side of the loader has always claimed to support mixed steppings. But somewhere along the way, it broke that by assuming that the cached patch blob is a single one instead of it being one per *node*. So turn it into a per-node one so that each node can stash the blob relevant for it. [ NB: Fixes tag is not really the exactly correct one but it is good enough. ] Fixes: fe055896c040 ("x86/microcode: Merge the early microcode loader") Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: <stable@kernel.org> # 2355370cd941 ("x86/microcode/amd: Remove load_microcode_amd()'s bsp parameter") Cc: <stable@kernel.org> # a5ad92134bd1 ("x86/microcode/AMD: Add a @cpu parameter to the reloading functions") Link: https://lore.kernel.org/r/20230130161709.11615-4-bp@alien8.de
2023-02-06x86/microcode/AMD: Add a @cpu parameter to the reloading functionsBorislav Petkov (AMD)
Will be used in a subsequent change. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20230130161709.11615-3-bp@alien8.de
2023-02-06x86/microcode/amd: Remove load_microcode_amd()'s bsp parameterBorislav Petkov (AMD)
It is always the BSP. No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20230130161709.11615-2-bp@alien8.de
2022-12-26x86/microcode/AMD: Handle multiple glued containers properlyBorislav Petkov
It can happen that - especially during testing - the microcode blobs of all families are all glued together in the initrd. The current code doesn't check whether the current container matched a microcode patch and continues to the next one, which leads to save_microcode_in_initrd_amd() to look at the next and thus wrong one: microcode: parse_container: ucode: 0xffff88807e9d9082 microcode: verify_patch: buf: 0xffff88807e9d90ce, buf_size: 26428 microcode: verify_patch: proc_id: 0x8082, patch_fam: 0x17, this family: 0x17 microcode: verify_patch: buf: 0xffff88807e9d9d56, buf_size: 23220 microcode: verify_patch: proc_id: 0x8012, patch_fam: 0x17, this family: 0x17 microcode: parse_container: MATCH: eq_id: 0x8012, patch proc_rev_id: 0x8012 <-- matching patch found microcode: verify_patch: buf: 0xffff88807e9da9de, buf_size: 20012 microcode: verify_patch: proc_id: 0x8310, patch_fam: 0x17, this family: 0x17 microcode: verify_patch: buf: 0xffff88807e9db666, buf_size: 16804 microcode: Invalid type field (0x414d44) in container file section header. microcode: Patch section fail <-- checking chokes on the microcode magic value of the next container. microcode: parse_container: saving container 0xffff88807e9d9082 microcode: save_microcode_in_initrd_amd: scanned containers, data: 0xffff88807e9d9082, size: 9700a and now if there's a next (and last container) it'll use that in save_microcode_in_initrd_amd() and not find a proper patch, ofc. Fix that by moving the out: label up, before the desc->mc check which jots down the pointer of the matching patch and is used to signal to the caller that it has found a matching patch in the current container. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20221219210656.5140-2-bp@alien8.de
2022-12-26x86/microcode/AMD: Rename a couple of functionsBorislav Petkov
- Rename apply_microcode_early_amd() to early_apply_microcode(): simplify the name so that it is clear what it does and when does it do it. - Rename __load_ucode_amd() to find_blobs_in_containers(): the new name actually explains what it does. Document some. No functional changes. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20221219210656.5140-1-bp@alien8.de
2022-12-13Merge tag 'x86_microcode_for_v6.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 microcode and IFS updates from Borislav Petkov: "The IFS (In-Field Scan) stuff goes through tip because the IFS driver uses the same structures and similar functionality as the microcode loader and it made sense to route it all through this branch so that there are no conflicts. - Add support for multiple testing sequences to the Intel In-Field Scan driver in order to be able to run multiple different test patterns. Rework things and remove the BROKEN dependency so that the driver can be enabled (Jithu Joseph) - Remove the subsys interface usage in the microcode loader because it is not really needed - A couple of smaller fixes and cleanups" * tag 'x86_microcode_for_v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits) x86/microcode/intel: Do not retry microcode reloading on the APs x86/microcode/intel: Do not print microcode revision and processor flags platform/x86/intel/ifs: Add missing kernel-doc entry Revert "platform/x86/intel/ifs: Mark as BROKEN" Documentation/ABI: Update IFS ABI doc platform/x86/intel/ifs: Add current_batch sysfs entry platform/x86/intel/ifs: Remove reload sysfs entry platform/x86/intel/ifs: Add metadata validation platform/x86/intel/ifs: Use generic microcode headers and functions platform/x86/intel/ifs: Add metadata support x86/microcode/intel: Use a reserved field for metasize x86/microcode/intel: Add hdr_type to intel_microcode_sanity_check() x86/microcode/intel: Reuse microcode_sanity_check() x86/microcode/intel: Use appropriate type in microcode_sanity_check() x86/microcode/intel: Reuse find_matching_signature() platform/x86/intel/ifs: Remove memory allocation from load path platform/x86/intel/ifs: Remove image loading during init platform/x86/intel/ifs: Return a more appropriate error code platform/x86/intel/ifs: Remove unused selection x86/microcode: Drop struct ucode_cpu_info.valid ...
2022-11-02x86/microcode: Kill refresh_fwBorislav Petkov
request_microcode_fw() can always request firmware now so drop this superfluous argument. Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Ashok Raj <ashok.raj@intel.com> Link: https://lore.kernel.org/r/20221028142638.28498-4-bp@alien8.de
2022-10-18x86/microcode/AMD: Apply the patch early on every logical threadBorislav Petkov
Currently, the patch application logic checks whether the revision needs to be applied on each logical CPU (SMT thread). Therefore, on SMT designs where the microcode engine is shared between the two threads, the application happens only on one of them as that is enough to update the shared microcode engine. However, there are microcode patches which do per-thread modification, see Link tag below. Therefore, drop the revision check and try applying on each thread. This is what the BIOS does too so this method is very much tested. Btw, change only the early paths. On the late loading paths, there's no point in doing per-thread modification because if is it some case like in the bugzilla below - removing a CPUID flag - the kernel cannot go and un-use features it has detected are there early. For that, one should use early loading anyway. [ bp: Fixes does not contain the oldest commit which did check for equality but that is good enough. ] Fixes: 8801b3fcb574 ("x86/microcode/AMD: Rework container parsing") Reported-by: Ștefan Talpalaru <stefantalpalaru@yahoo.com> Signed-off-by: Borislav Petkov <bp@suse.de> Tested-by: Ștefan Talpalaru <stefantalpalaru@yahoo.com> Cc: <stable@vger.kernel.org> Link: https://bugzilla.kernel.org/show_bug.cgi?id=216211
2022-09-23x86/microcode/AMD: Track patch allocation size explicitlyKees Cook
In preparation for reducing the use of ksize(), record the actual allocation size for later memcpy(). This avoids copying extra (uninitialized!) bytes into the patch buffer when the requested allocation size isn't exactly the size of a kmalloc bucket. Additionally, fix potential future issues where runtime bounds checking will notice that the buffer was allocated to a smaller value than returned by ksize(). Fixes: 757885e94a22 ("x86, microcode, amd: Early microcode patch loading support for AMD") Suggested-by: Daniel Micay <danielmicay@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/lkml/CA+DvKQ+bp7Y7gmaVhacjv9uF6Ar-o4tet872h4Q8RPYPJjcJQA@mail.gmail.com/
2022-08-26x86/microcode: Remove ->request_microcode_user()Borislav Petkov
181b6f40e9ea ("x86/microcode: Rip out the OLD_INTERFACE") removed the old microcode loading interface but forgot to remove the related ->request_microcode_user() functionality which it uses. Rip it out now too. Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/20220825075445.28171-1-bp@alien8.de
2021-10-22x86/microcode: Use the firmware_loader built-in APIBorislav Petkov
The microcode loader has been looping through __start_builtin_fw down to __end_builtin_fw to look for possibly built-in firmware for microcode updates. Now that the firmware loader code has exported an API for looping through the kernel's built-in firmware section, use it and drop the x86 implementation in favor. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Link: https://lore.kernel.org/r/20211021155843.1969401-4-mcgrof@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-26x86/microcode/amd: Remove unneeded breakTom Rix
A break is not needed if it is preceded by a return. Signed-off-by: Tom Rix <trix@redhat.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20201019200629.17247-1-trix@redhat.com
2019-10-01x86/microcode/amd: Fix two -Wunused-but-set-variable warningsBorislav Petkov
The dummy variable is the high part of the microcode revision MSR which is defined as reserved. Mark it unused so that W=1 builds don't trigger the above warning. No functional changes. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: x86@kernel.org Link: https://lkml.kernel.org/r/20190928162559.26294-1-bp@alien8.de