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5 daysMerge tag 'soc-drivers-6.19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc Pull SoC driver updates from Arnd Bergmann: "This is the first half of the driver changes: - A treewide interface change to the "syscore" operations for power management, as a preparation for future Tegra specific changes - Reset controller updates with added drivers for LAN969x, eic770 and RZ/G3S SoCs - Protection of system controller registers on Renesas and Google SoCs, to prevent trivially triggering a system crash from e.g. debugfs access - soc_device identification updates on Nvidia, Exynos and Mediatek - debugfs support in the ST STM32 firewall driver - Minor updates for SoC drivers on AMD/Xilinx, Renesas, Allwinner, TI - Cleanups for memory controller support on Nvidia and Renesas" * tag 'soc-drivers-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (114 commits) memory: tegra186-emc: Fix missing put_bpmp Documentation: reset: Remove reset_controller_add_lookup() reset: fix BIT macro reference reset: rzg2l-usbphy-ctrl: Fix a NULL vs IS_ERR() bug in probe reset: th1520: Support reset controllers in more subsystems reset: th1520: Prepare for supporting multiple controllers dt-bindings: reset: thead,th1520-reset: Add controllers for more subsys dt-bindings: reset: thead,th1520-reset: Remove non-VO-subsystem resets reset: remove legacy reset lookup code clk: davinci: psc: drop unused reset lookup reset: rzg2l-usbphy-ctrl: Add support for RZ/G3S SoC reset: rzg2l-usbphy-ctrl: Add support for USB PWRRDY dt-bindings: reset: renesas,rzg2l-usbphy-ctrl: Document RZ/G3S support reset: eswin: Add eic7700 reset driver dt-bindings: reset: eswin: Documentation for eic7700 SoC reset: sparx5: add LAN969x support dt-bindings: reset: microchip: Add LAN969x support soc: rockchip: grf: Add select correct PWM implementation on RK3368 soc/tegra: pmc: Add USB wake events for Tegra234 amba: tegra-ahb: Fix device leak on SMMU enable ...
8 daysMerge tag 'x86_microcode_for_v6.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 microcode loading updates from Borislav Petkov: - Add microcode staging support on Intel: it moves the sole microcode blobs loading to a non-critical path so that microcode loading latencies are kept at minimum. The actual "directing" the hardware to load microcode is the only step which is done on the critical path. This scheme is also opportunistic as in: on a failure, the machinery falls back to normal loading - Add the capability to the AMD side of the loader to select one of two per-family/model/stepping patches: one is pre-Entrysign and the other is post-Entrysign; with the goal to take care of machines which haven't updated their BIOS yet - something they should absolutely do as this is the only proper Entrysign fix - Other small cleanups and fixlets * tag 'x86_microcode_for_v6.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/microcode: Mark early_parse_cmdline() as __init x86/microcode/AMD: Select which microcode patch to load x86/microcode/intel: Enable staging when available x86/microcode/intel: Support mailbox transfer x86/microcode/intel: Implement staging handler x86/microcode/intel: Define staging state struct x86/microcode/intel: Establish staging control logic x86/microcode: Introduce staging step to reduce late-loading time x86/cpu/topology: Make primary thread mask available with SMP=n
2025-11-14x86/microcode/AMD: Add Zen5 model 0x44, stepping 0x1 minrevBorislav Petkov (AMD)
Add the minimum Entrysign revision for that model+stepping to the list of minimum revisions. Fixes: 50cef76d5cb0 ("x86/microcode/AMD: Load only SHA256-checksummed patches") Reported-by: Andrew Cooper <andrew.cooper3@citrix.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: <stable@kernel.org> Link: https://lore.kernel.org/r/e94dd76b-4911-482f-8500-5c848a3df026@citrix.com
2025-11-14syscore: Pass context data to callbacksThierry Reding
Several drivers can benefit from registering per-instance data along with the syscore operations. To achieve this, move the modifiable fields out of the syscore_ops structure and into a separate struct syscore that can be registered with the framework. Add a void * driver data field for drivers to store contextual data that will be passed to the syscore ops. Acked-by: Rafael J. Wysocki (Intel) <rafael@kernel.org> Signed-off-by: Thierry Reding <treding@nvidia.com>
2025-11-07x86/microcode/AMD: Add more known models to entry sign checkingMario Limonciello (AMD)
Two Zen5 systems are missing from need_sha_check(). Add them. Fixes: 50cef76d5cb0 ("x86/microcode/AMD: Load only SHA256-checksummed patches") Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: <stable@kernel.org> Link: https://patch.msgid.link/20251106182904.4143757-1-superm1@kernel.org
2025-10-30x86/microcode: Mark early_parse_cmdline() as __initYu Peng
Fix section mismatch warning reported by modpost: .text:early_parse_cmdline() -> .init.data:boot_command_line The function early_parse_cmdline() is only called during init and accesses init data, so mark it __init to match its usage. [ bp: This happens only when the toolchain fails to inline the function and I haven't been able to reproduce it with any toolchain I'm using. Patch is obviously correct regardless. ] Signed-off-by: Yu Peng <pengyu@kylinos.cn> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://patch.msgid.link/all/20251030123757.1410904-1-pengyu@kylinos.cn
2025-10-30x86/microcode/AMD: Select which microcode patch to loadBorislav Petkov (AMD)
All microcode patches up to the proper BIOS Entrysign fix are loaded only after the sha256 signature carried in the driver has been verified. Microcode patches after the Entrysign fix has been applied, do not need that signature verification anymore. In order to not abandon machines which haven't received the BIOS update yet, add the capability to select which microcode patch to load. The corresponding microcode container supplied through firmware-linux has been modified to carry two patches per CPU type (family/model/stepping) so that the proper one gets selected. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Waiman Long <longman@redhat.com> Link: https://patch.msgid.link/20251027133818.4363-1-bp@kernel.org
2025-10-27x86/microcode/AMD: Limit Entrysign signature checking to known generationsBorislav Petkov (AMD)
Limit Entrysign sha256 signature checking to CPUs in the range Zen1-Zen5. X86_BUG cannot be used here because the loading on the BSP happens way too early, before the cpufeatures machinery has been set up. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://patch.msgid.link/all/20251023124629.5385-1-bp@kernel.org
2025-10-27Merge tag 'x86_urgent_for_v6.18_rc3' into x86/microcodeBorislav Petkov (AMD)
Pick up the below urgent upstream change in order to base more work ontop: - Correct the last Zen1 microcode revision for which Entrysign sha256 check is needed Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2025-10-21x86/microcode: Fix Entrysign revision check for Zen1/NaplesAndrew Cooper
... to match AMD's statement here: https://www.amd.com/en/resources/product-security/bulletin/amd-sb-7033.html Fixes: 50cef76d5cb0 ("x86/microcode/AMD: Load only SHA256-checksummed patches") Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: <stable@kernel.org> Link: https://patch.msgid.link/20251020144124.2930784-1-andrew.cooper3@citrix.com
2025-10-15x86/microcode/intel: Enable staging when availableChang S. Bae
With staging support implemented, enable it when the CPU reports the feature. [ bp: Sort in the MSR properly. ] Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Chao Gao <chao.gao@intel.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Tested-by: Anselm Busse <abusse@amazon.de> Link: https://lore.kernel.org/20250320234104.8288-1-chang.seok.bae@intel.com
2025-10-15x86/microcode/intel: Support mailbox transferChang S. Bae
The functions for sending microcode data and retrieving the next offset were previously placeholders, as they need to handle a specific mailbox format. While the kernel supports similar mailboxes, none of them are compatible with this one. Attempts to share code led to unnecessary complexity, so add a dedicated implementation instead. [ bp: Sort the include properly. ] Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Tested-by: Anselm Busse <abusse@amazon.de> Link: https://lore.kernel.org/20250320234104.8288-1-chang.seok.bae@intel.com
2025-10-15x86/microcode/intel: Implement staging handlerChang S. Bae
Previously, per-package staging invocations and their associated state data were established. The next step is to implement the actual staging handler according to the specified protocol. Below are key aspects to note: (a) Each staging process must begin by resetting the staging hardware. (b) The staging hardware processes up to a page-sized chunk of the microcode image per iteration, requiring software to submit data incrementally. (c) Once a data chunk is processed, the hardware responds with an offset in the image for the next chunk. (d) The offset may indicate completion or request retransmission of an already transferred chunk. As long as the total transferred data remains within the predefined limit (twice the image size), retransmissions should be acceptable. Incorporate them in the handler, while data transmission and mailbox format handling are implemented separately. [ bp: Sort the headers in a reversed name-length order. ] Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Tested-by: Anselm Busse <abusse@amazon.de> Link: https://lore.kernel.org/20250320234104.8288-1-chang.seok.bae@intel.com
2025-10-15x86/microcode/intel: Define staging state structChang S. Bae
Define a staging_state struct to simplify function prototypes by consolidating relevant data, instead of passing multiple local variables. Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Tested-by: Anselm Busse <abusse@amazon.de> Link: https://lore.kernel.org/20250320234104.8288-1-chang.seok.bae@intel.com
2025-10-15x86/microcode/intel: Establish staging control logicChang S. Bae
When microcode staging is initiated, operations are carried out through an MMIO interface. Each package has a unique interface specified by the IA32_MCU_STAGING_MBOX_ADDR MSR, which maps to a set of 32-bit registers. Prepare staging with the following steps: 1. Ensure the microcode image is 32-bit aligned to match the MMIO register size. 2. Identify each MMIO interface based on its per-package scope. 3. Invoke the staging function for each identified interface, which will be implemented separately. [ bp: Improve error logging. ] Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Tested-by: Anselm Busse <abusse@amazon.de> Link: https://lore.kernel.org/all/871pznq229.ffs@tglx
2025-10-15x86/microcode: Introduce staging step to reduce late-loading timeChang S. Bae
As microcode patch sizes continue to grow, late-loading latency spikes can lead to timeouts and disruptions in running workloads. This trend of increasing patch sizes is expected to continue, so a foundational solution is needed to address the issue. To mitigate the problem, introduce a microcode staging feature. This option processes most of the microcode update (excluding activation) on a non-critical path, allowing CPUs to remain operational during the majority of the update. By offloading work from the critical path, staging can significantly reduce latency spikes. Integrate staging as a preparatory step in late-loading. Introduce a new callback for staging, which is invoked at the beginning of load_late_stop_cpus(), before CPUs enter the rendezvous phase. Staging follows an opportunistic model: * If successful, it reduces CPU rendezvous time * Even though it fails, the process falls back to the legacy path to finish the loading process but with potentially higher latency. Extend struct microcode_ops to incorporate staging properties, which will be implemented in the vendor code separately. Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Chao Gao <chao.gao@intel.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Tested-by: Anselm Busse <abusse@amazon.de> Link: https://lore.kernel.org/20250320234104.8288-1-chang.seok.bae@intel.com
2025-09-04x86/microcode: Add microcode loader debugging functionalityBorislav Petkov (AMD)
Instead of adding ad-hoc debugging glue to the microcode loader each time I need it, add debugging functionality which is not built by default. Simulate all patch handling the loader does except the actual loading of the microcode patch into the hardware. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/20250820135043.19048-3-bp@kernel.org
2025-09-04x86/microcode: Add microcode= cmdline parsingBorislav Petkov (AMD)
Add a "microcode=" command line argument after which all options can be passed in a comma-separated list. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Sohil Mehta <sohil.mehta@intel.com> Reviewed-by: Chang S. Bae <chang.seok.bae@intel.com> Link: https://lore.kernel.org/20250820135043.19048-2-bp@kernel.org
2025-09-04x86/microcode/intel: Refresh the revisions that determine old_microcodeSohil Mehta
Update the minimum expected revisions of Intel microcode based on the microcode-20250512 (May 2025) release. Signed-off-by: Sohil Mehta <sohil.mehta@intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/all/20250818190137.3525414-2-sohil.mehta%40intel.com
2025-08-27x86/microcode/AMD: Handle the case of no BIOS microcodeBorislav Petkov (AMD)
Machines can be shipped without any microcode in the BIOS. Which means, the microcode patch revision is 0. Handle that gracefully. Fixes: 94838d230a6c ("x86/microcode/AMD: Use the family,model,stepping encoded in the patch ID") Reported-by: Vítek Vávra <vit.vavra.kh@gmail.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: <stable@kernel.org>
2025-07-29Merge tag 'x86_microcode_for_v6.17_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 microcode loader update from Borislav Petkov: - Switch the microcode loader from using the fake platform device to the new simple faux bus * tag 'x86_microcode_for_v6.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/microcode: Move away from using a fake platform device
2025-07-09x86/microcode: Move away from using a fake platform deviceGreg Kroah-Hartman
Downloading firmware needs a device to hang off of, and so a platform device seemed like the simplest way to do this. Now that we have a faux device interface, use that instead as this "microcode device" is not anything resembling a platform device at all. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Sohil Mehta <sohil.mehta@intel.com> Link: https://lore.kernel.org/2025070121-omission-small-9308@gregkh
2025-06-17x86/microcode/AMD: Add TSA microcode SHAsBorislav Petkov (AMD)
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2025-05-15x86/cpuid: Rename have_cpuid_p() to cpuid_feature()Ahmed S. Darwish
In order to let all the APIs under <cpuid/api.h> have a shared "cpuid_" namespace, rename have_cpuid_p() to cpuid_feature(). Adjust all call-sites accordingly. Suggested-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Andrew Cooper <andrew.cooper3@citrix.com> Cc: John Ogness <john.ogness@linutronix.de> Cc: x86-cpuid@lists.linux.dev Link: https://lore.kernel.org/r/20250508150240.172915-4-darwi@linutronix.de
2025-05-13Merge branch 'x86/msr' into x86/core, to resolve conflictsIngo Molnar
Conflicts: arch/x86/boot/startup/sme.c arch/x86/coco/sev/core.c arch/x86/kernel/fpu/core.c arch/x86/kernel/fpu/xstate.c Semantic conflict: arch/x86/include/asm/sev-internal.h Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-05-13Merge branch 'x86/microcode' into x86/core, to merge dependent commitsIngo Molnar
Prepare to resolve conflicts with an upstream series of fixes that conflict with pending x86 changes: 6f5bf947bab0 Merge tag 'its-for-linus-20250509' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-05-05x86/microcode: Consolidate the loader enablement checkingBorislav Petkov (AMD)
Consolidate the whole logic which determines whether the microcode loader should be enabled or not into a single function and call it everywhere. Well, almost everywhere - not in mk_early_pgtbl_32() because there the kernel is running without paging enabled and checking dis_ucode_ldr et al would require physical addresses and uglification of the code. But since this is 32-bit, the easier thing to do is to simply map the initrd unconditionally especially since that mapping is getting removed later anyway by zap_early_initrd_mapping() and avoid the uglification. In doing so, address the issue of old 486er machines without CPUID support, not booting current kernels. [ mingo: Fix no previous prototype for ‘microcode_loader_disabled’ [-Wmissing-prototypes] ] Fixes: 4c585af7180c1 ("x86/boot/32: Temporarily map initrd for microcode loading") Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: <stable@kernel.org> Link: https://lore.kernel.org/r/CANpbe9Wm3z8fy9HbgS8cuhoj0TREYEEkBipDuhgkWFvqX0UoVQ@mail.gmail.com
2025-05-02x86/msr: Add explicit includes of <asm/msr.h>Xin Li (Intel)
For historic reasons there are some TSC-related functions in the <asm/msr.h> header, even though there's an <asm/tsc.h> header. To facilitate the relocation of rdtsc{,_ordered}() from <asm/msr.h> to <asm/tsc.h> and to eventually eliminate the inclusion of <asm/msr.h> in <asm/tsc.h>, add an explicit <asm/msr.h> dependency to the source files that reference definitions from <asm/msr.h>. [ mingo: Clarified the changelog. ] Signed-off-by: Xin Li (Intel) <xin@zytor.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: Juergen Gross <jgross@suse.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Kees Cook <keescook@chromium.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Uros Bizjak <ubizjak@gmail.com> Link: https://lore.kernel.org/r/20250501054241.1245648-1-xin@zytor.com
2025-05-02Merge tag 'v6.15-rc4' into x86/msr, to pick up fixes and resolve conflictsIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-04-30x86/microcode/AMD: Do not return error when microcode update is not necessaryAnnie Li
After 6f059e634dcd("x86/microcode: Clarify the late load logic"), if the load is up-to-date, the AMD side returns UCODE_OK which leads to load_late_locked() returning -EBADFD. Handle UCODE_OK in the switch case to avoid this error. [ bp: Massage commit message. ] Fixes: 6f059e634dcd ("x86/microcode: Clarify the late load logic") Signed-off-by: Annie Li <jiayanli@google.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/20250430053424.77438-1-jiayanli@google.com
2025-04-28x86/microcode/AMD: Use sha256() instead of init/update/finalEric Biggers
Just call sha256() instead of doing the init/update/final sequence. No functional changes. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/20250428183006.782501-1-ebiggers@kernel.org
2025-04-22x86/cpu: Help users notice when running old Intel microcodeDave Hansen
Old microcode is bad for users and for kernel developers. For users, it exposes them to known fixed security and/or functional issues. These obviously rarely result in instant dumpster fires in every environment. But it is as important to keep your microcode up to date as it is to keep your kernel up to date. Old microcode also makes kernels harder to debug. A developer looking at an oops need to consider kernel bugs, known CPU issues and unknown CPU issues as possible causes. If they know the microcode is up to date, they can mostly eliminate known CPU issues as the cause. Make it easier to tell if CPU microcode is out of date. Add a list of released microcode. If the loaded microcode is older than the release, tell users in a place that folks can find it: /sys/devices/system/cpu/vulnerabilities/old_microcode Tell kernel kernel developers about it with the existing taint flag: TAINT_CPU_OUT_OF_SPEC == Discussion == When a user reports a potential kernel issue, it is very common to ask them to reproduce the issue on mainline. Running mainline, they will (independently from the distro) acquire a more up-to-date microcode version list. If their microcode is old, they will get a warning about the taint and kernel developers can take that into consideration when debugging. Just like any other entry in "vulnerabilities/", users are free to make their own assessment of their exposure. == Microcode Revision Discussion == The microcode versions in the table were generated from the Intel microcode git repo: 8ac9378a8487 ("microcode-20241112 Release") which as of this writing lags behind the latest microcode-20250211. It can be argued that the versions that the kernel picks to call "old" should be a revision or two old. Which specific version is picked is less important to me than picking *a* version and enforcing it. This repository contains only microcode versions that Intel has deemed to be OS-loadable. It is quite possible that the BIOS has loaded a newer microcode than the latest in this repo. If this happens, the system is considered to have new microcode, not old. Specifically, the sysfs file and taint flag answer the question: Is the CPU running on the latest OS-loadable microcode, or something even later that the BIOS loaded? In other words, Intel never publishes an authoritative list of CPUs and latest microcode revisions. Until it does, this is the best that Linux can do. Also note that the "intel-ucode-defs.h" file is simple, ugly and has lots of magic numbers. That's on purpose and should allow a single file to be shared across lots of stable kernel regardless of if they have the new "VFM" infrastructure or not. It was generated with a dumb script. == FAQ == Q: Does this tell me if my system is secure or insecure? A: No. It only tells you if your microcode was old when the system booted. Q: Should the kernel warn if the microcode list itself is too old? A: No. New kernels will get new microcode lists, both mainline and stable. The only way to have an old list is to be running an old kernel in which case you have bigger problems. Q: Is this for security or functional issues? A: Both. Q: If a given microcode update only has functional problems but no security issues, will it be considered old? A: Yes. All microcode image versions within a microcode release are treated identically. Intel appears to make security updates without disclosing them in the release notes. Thus, all updates are considered to be security-relevant. Q: Who runs old microcode? A: Anybody with an old distro. This happens all the time inside of Intel where there are lots of weird systems in labs that might not be getting regular distro updates and might also be running rather exotic microcode images. Q: If I update my microcode after booting will it stop saying "Vulnerable"? A: No. Just like all the other vulnerabilies, you need to reboot before the kernel will reassess your vulnerability. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: "Ahmed S. Darwish" <darwi@linutronix.de> Cc: Andrew Cooper <andrew.cooper3@citrix.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: John Ogness <john.ogness@linutronix.de> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/all/20250421195659.CF426C07%40davehans-spike.ostc.intel.com (cherry picked from commit 9127865b15eb0a1bd05ad7efe29489c44394bdc1)
2025-04-12x86/microcode/AMD: Extend the SHA check to Zen5, block loading of any ↵Borislav Petkov (AMD)
unreleased standalone Zen5 microcode patches All Zen5 machines out there should get BIOS updates which update to the correct microcode patches addressing the microcode signature issue. However, silly people carve out random microcode blobs from BIOS packages and think are doing other people a service this way... Block loading of any unreleased standalone Zen5 microcode patches. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: <stable@kernel.org> Cc: Andrew Cooper <andrew.cooper3@citrix.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Maciej S. Szmigiero <mail@maciej.szmigiero.name> Cc: Nikolay Borisov <nik.borisov@suse.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lore.kernel.org/r/20250410114222.32523-1-bp@kernel.org
2025-04-10x86/msr: Rename 'native_wrmsrl()' to 'native_wrmsrq()'Ingo Molnar
Suggested-by: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Juergen Gross <jgross@suse.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Xin Li <xin@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org>
2025-04-07x86/microcode/AMD: Clean the cache if update did not load microcodeBoris Ostrovsky
If microcode did not get loaded there is no reason to keep it in the cache. Moreover, if loading failed it will not be possible to load an earlier version of microcode since the failed revision will always be selected from the cache on the next reload attempt. Since the failed revisions is not easily available at this point just clean the whole cache. It will be rebuilt later if needed. Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20250327230503.1850368-3-boris.ostrovsky@oracle.com
2025-03-28x86/microcode/AMD: Fix __apply_microcode_amd()'s return valueBoris Ostrovsky
When verify_sha256_digest() fails, __apply_microcode_amd() should propagate the failure by returning false (and not -1 which is promoted to true). Fixes: 50cef76d5cb0 ("x86/microcode/AMD: Load only SHA256-checksummed patches") Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20250327230503.1850368-2-boris.ostrovsky@oracle.com
2025-03-19x86/microcode: Update the Intel processor flag scan checkSohil Mehta
The Family model check to read the processor flag MSR is misleading and potentially incorrect. It doesn't consider Family while comparing the model number. The original check did have a Family number but it got lost/moved during refactoring. intel_collect_cpu_info() is called through multiple paths such as early initialization, CPU hotplug as well as IFS image load. Some of these flows would be error prone due to the ambiguous check. Correct the processor flag scan check to use a Family number and update it to a VFM based one to make it more readable. Signed-off-by: Sohil Mehta <sohil.mehta@intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lore.kernel.org/r/20250219184133.816753-4-sohil.mehta@intel.com
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