Commit Graph

386 Commits

Author SHA1 Message Date
Borislav Petkov (AMD)
ac44a110c1 x86/microcode/AMD: Allow loader debugging to be enabled on baremetal too
Debugging the loader on baremetal does make sense, so enable it there
too.

Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://patch.msgid.link/20260108165028.27417-1-bp@kernel.org
2026-01-14 14:46:44 +01:00
Rong Zhang
150b1b97e2 x86/microcode/AMD: Fix Entrysign revision check for Zen5/Strix Halo
Zen5 also contains family 1Ah, models 70h-7Fh, which are mistakenly missing
from cpu_has_entrysign(). Add the missing range.

Fixes: 8a9fb5129e ("x86/microcode/AMD: Limit Entrysign signature checking to known generations")
Signed-off-by: Rong Zhang <i@rong.moe>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: stable@kernel.org
Link: https://patch.msgid.link/20251229182245.152747-1-i@rong.moe
2025-12-29 20:08:02 +01:00
Linus Torvalds
208eed95fc Merge tag 'soc-drivers-6.19' of 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
  ...
2025-12-05 17:29:04 -08:00
Linus Torvalds
2a47c26e55 Merge tag 'x86_microcode_for_v6.19_rc1' of 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
2025-12-02 11:35:49 -08:00
Borislav Petkov (AMD)
dd14022a7c x86/microcode/AMD: Add Zen5 model 0x44, stepping 0x1 minrev
Add the minimum Entrysign revision for that model+stepping to the list
of minimum revisions.

Fixes: 50cef76d5c ("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
2025-11-14 14:04:49 +01:00
Thierry Reding
a97fbc3ee3 syscore: Pass context data to callbacks
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>
2025-11-14 10:01:52 +01:00
Mario Limonciello (AMD)
d23550efc6 x86/microcode/AMD: Add more known models to entry sign checking
Two Zen5 systems are missing from need_sha_check(). Add them.

Fixes: 50cef76d5c ("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
2025-11-07 12:12:21 +01:00
Yu Peng
ca8313fd83 x86/microcode: Mark early_parse_cmdline() as __init
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
2025-10-30 14:33:31 +01:00
Borislav Petkov (AMD)
8d17104506 x86/microcode/AMD: Select which microcode patch to load
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
2025-10-30 14:29:54 +01:00
Borislav Petkov (AMD)
8a9fb5129e x86/microcode/AMD: Limit Entrysign signature checking to known generations
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
2025-10-27 17:07:17 +01:00
Borislav Petkov (AMD)
4058386498 Merge tag 'x86_urgent_for_v6.18_rc3' into x86/microcode
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>
2025-10-27 14:06:38 +01:00
Andrew Cooper
876f0d43af x86/microcode: Fix Entrysign revision check for Zen1/Naples
... to match AMD's statement here:

https://www.amd.com/en/resources/product-security/bulletin/amd-sb-7033.html

Fixes: 50cef76d5c ("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
2025-10-21 12:16:51 +02:00
Chang S. Bae
bffeb2fd0b x86/microcode/intel: Enable staging when available
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
2025-10-15 16:47:50 +02:00
Chang S. Bae
4ab410287b x86/microcode/intel: Support mailbox transfer
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
2025-10-15 16:47:43 +02:00
Chang S. Bae
afc3b50954 x86/microcode/intel: Implement staging handler
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
2025-10-15 16:47:37 +02:00
Chang S. Bae
079b90d4ba x86/microcode/intel: Define staging state struct
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
2025-10-15 16:47:31 +02:00
Chang S. Bae
740144bc6b x86/microcode/intel: Establish staging control logic
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
2025-10-15 16:47:20 +02:00
Chang S. Bae
7cdda85ed9 x86/microcode: Introduce staging step to reduce late-loading time
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
2025-10-15 16:46:58 +02:00
Borislav Petkov (AMD)
43181a4726 x86/microcode: Add microcode loader debugging functionality
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
2025-09-04 16:15:19 +02:00
Borislav Petkov (AMD)
632ff61706 x86/microcode: Add microcode= cmdline parsing
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
2025-09-04 16:02:20 +02:00
Sohil Mehta
855042367e x86/microcode/intel: Refresh the revisions that determine old_microcode
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
2025-09-04 15:57:17 +02:00
Borislav Petkov (AMD)
fcf8239ad6 x86/microcode/AMD: Handle the case of no BIOS microcode
Machines can be shipped without any microcode in the BIOS. Which means,
the microcode patch revision is 0.

Handle that gracefully.

Fixes: 94838d230a ("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>
2025-08-27 10:24:10 +02:00
Linus Torvalds
01fce21e1a Merge tag 'x86_microcode_for_v6.17_rc1' of 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
2025-07-29 17:16:26 -07:00
Greg Kroah-Hartman
9b355cdb63 x86/microcode: Move away from using a fake platform device
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
2025-07-09 13:12:08 +02:00
Borislav Petkov (AMD)
2329f250e0 x86/microcode/AMD: Add TSA microcode SHAs
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2025-06-17 17:17:12 +02:00
Ahmed S. Darwish
2f924ca36d x86/cpuid: Rename have_cpuid_p() to cpuid_feature()
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
2025-05-15 18:23:55 +02:00
Ingo Molnar
1f82e8e1ca Merge branch 'x86/msr' into x86/core, to resolve conflicts
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>
2025-05-13 10:42:06 +02:00
Ingo Molnar
69cb33e2f8 Merge branch 'x86/microcode' into x86/core, to merge dependent commits
Prepare to resolve conflicts with an upstream series of fixes that conflict
with pending x86 changes:

  6f5bf947ba 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>
2025-05-13 10:37:52 +02:00
Borislav Petkov (AMD)
5214a9f6c0 x86/microcode: Consolidate the loader enablement checking
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: 4c585af718 ("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
2025-05-05 10:51:00 +02:00
Xin Li (Intel)
efef7f184f x86/msr: Add explicit includes of <asm/msr.h>
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
2025-05-02 10:23:47 +02:00
Ingo Molnar
0c7b20b852 Merge tag 'v6.15-rc4' into x86/msr, to pick up fixes and resolve conflicts
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-05-02 09:43:44 +02:00
Annie Li
b43dc4ab09 x86/microcode/AMD: Do not return error when microcode update is not necessary
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: 6f059e634d ("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
2025-04-30 17:10:46 +02:00
Eric Biggers
c0a62eadb6 x86/microcode/AMD: Use sha256() instead of init/update/final
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
2025-04-28 21:03:58 +02:00
Dave Hansen
4e2c719782 x86/cpu: Help users notice when running old Intel microcode
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)
2025-04-22 08:33:52 +02:00
Borislav Petkov (AMD)
805b743fc1 x86/microcode/AMD: Extend the SHA check to Zen5, block loading of any 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
2025-04-12 21:09:42 +02:00
Ingo Molnar
7cbc2ba7c1 x86/msr: Rename 'native_wrmsrl()' to 'native_wrmsrq()'
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>
2025-04-10 11:59:28 +02:00
Boris Ostrovsky
321550859f x86/microcode/AMD: Clean the cache if update did not load microcode
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
2025-04-07 14:46:56 +02:00
Boris Ostrovsky
31ab12df72 x86/microcode/AMD: Fix __apply_microcode_amd()'s return value
When verify_sha256_digest() fails, __apply_microcode_amd() should propagate
the failure by returning false (and not -1 which is promoted to true).

Fixes: 50cef76d5c ("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
2025-03-28 12:49:02 +01:00
Sohil Mehta
7e6b0a2e41 x86/microcode: Update the Intel processor flag scan check
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
2025-03-19 11:19:38 +01:00
Florent Revest
e3e89178a9 x86/microcode/AMD: Fix out-of-bounds on systems with CPU-less NUMA nodes
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: 7ff6edf4fe ("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
2025-03-10 16:02:54 +01:00
Borislav Petkov (AMD)
058a6bec37 x86/microcode/AMD: Add some forgotten models to the SHA check
Add some more forgotten models to the SHA check.

Fixes: 50cef76d5c ("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
2025-03-08 20:09:37 +01:00
Borislav Petkov (AMD)
50cef76d5c x86/microcode/AMD: Load only SHA256-checksummed patches
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>
2025-02-22 11:46:05 +01:00
Borislav Petkov (AMD)
037e81fb9d x86/microcode/AMD: Add get_patch_level()
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
2025-02-17 09:42:40 +01:00
Borislav Petkov (AMD)
b39c387164 x86/microcode/AMD: Get rid of the _load_microcode_amd() forward declaration
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
2025-02-17 09:42:37 +01:00
Borislav Petkov (AMD)
dc15675074 x86/microcode/AMD: Merge early_apply_microcode() into its single callsite
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
2025-02-17 09:42:34 +01:00
Borislav Petkov (AMD)
3ef0740d10 x86/microcode/AMD: Remove unused save_microcode_in_initrd_amd() declarations
Commit

  a7939f0167 ("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
2025-02-17 09:42:31 +01:00
Borislav Petkov (AMD)
7103f0589a x86/microcode/AMD: Remove ugly linebreak in __verify_patch_section() signature
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
2025-02-17 09:42:13 +01:00
Borislav Petkov (AMD)
ead0db14c7 x86/microcode/AMD: Remove ret local var in early_apply_microcode()
No functional changes.

Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2024-12-31 14:03:41 +01:00
Borislav Petkov (AMD)
78e0aadbd4 x86/microcode/AMD: Have __apply_microcode_amd() return bool
This is the natural thing to do anyway.

No functional changes.

Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2024-12-31 14:03:39 +01:00
Nikolay Borisov
d8317f3d8e x86/microcode/AMD: Make __verify_patch_size() return bool
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
2024-12-31 14:03:37 +01:00