Pull x86 microcode loader updates from Borislav Petkov:
- Move the zero-revision fixup for AMD microcode to the patch level
retrieval function and restrict it to Zen family processors, ensuring
patch level arithmetic always operates on a valid revision
- Fix an incorrect comment about which CPUID bit is checked when
determining whether the microcode loader should be disabled
- Add the latest Intel microcode revision data for a broad range of
processor models and steppings and add the script which generates the
header of minimum expected Intel microcode revisions
* tag 'x86_microcode_for_v7.2_rc1' of gitolite.kernel.org:pub/scm/linux/kernel/git/tip/tip:
x86/microcode/AMD: Move the no-revision fixup to get_patch_level()
x86/microcode: Fix comment in microcode_loader_disabled()
scripts/x86/intel: Add a script to update the old microcode list
x86/microcode/intel: Refresh old_microcode defines with Nov 2025 release
Pull x86 cpuid updates from Ingo Molnar:
- CPUID API updates (Ahmed S. Darwish):
- Introduce a centralized CPUID parser
- Introduce a centralized CPUID data model
- Introduce <asm/cpuid/leaf_types.h>
- Rename cpuid_leaf()/cpuid_subleaf() APIs
- treewide: Explicitly include the x86 CPUID headers
- Update to x86-cpuid-db v3.1 (Maciej Wieczor-Retman)
- Continued removal of pre-i586 support and related simplifications
(Ingo Molnar)
- Add Intel CPU model number for rugged Panther Lake (Tony Luck)
- Misc fixes, updates and cleanups by Arnd Bergmann, Chao Gao, Lukas
Bulwahn, Sohil Mehta, Maciej Wieczor-Retman.
* tag 'x86-cpu-2026-06-14' of gitolite.kernel.org:pub/scm/linux/kernel/git/tip/tip: (25 commits)
x86/cpu: Make CONFIG_X86_CX8 unconditional
x86/cpu: Remove unused !CONFIG_X86_TSC code
x86/cpuid: Update bitfields to x86-cpuid-db v3.1
tools/x86/kcpuid: Update bitfields to x86-cpuid-db v3.1
x86/cpu: Make CONFIG_X86_TSC unconditional
MAINTAINERS: Drop obsolete FPU EMULATOR section
x86/cpu: Fix a F00F bug warning and clean up surrounding code
x86/cpu: Add Intel CPU model number for rugged Panther Lake
x86/cpuid: Introduce a centralized CPUID parser
x86/cpu: Introduce a centralized CPUID data model
x86/cpuid: Introduce <asm/cpuid/leaf_types.h>
x86/cpuid: Rename cpuid_leaf()/cpuid_subleaf() APIs
x86/cpu: Do not include the CPUID API header in asm/processor.h
Documentation: core-api/cpu_hotplug: Remove stale cpu0_hotplug docs
x86/cpu, cpufreq: Remove AMD ELAN support
x86/fpu: Remove the math-emu/ FPU emulation library
x86/fpu: Remove the 'no387' boot option
x86/fpu: Remove MATH_EMULATION and related glue code
treewide: Explicitly include the x86 CPUID headers
x86/cpu: Remove the CONFIG_X86_INVD_BUG quirk
...
On machines which don't have microcode applied yet, the revision is 0.
However, this doesn't work with the Zen family/model/stepping patch
arithmetic. So move the fixup to the patch level getter function and
this way make sure the patch level is always proper and thus the
arithmetic always works.
And now that it can be called on any family, make this Zen-only.
Assisted-by: claude/claude-opus-4-6
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20260530024213.86137-1-bp@kernel.org
Patch in Fixes: causes the usual:
unchecked MSR access error: RDMSR from 0x17 at ... (intel_get_platform_id)
Call Trace:
early_init_intel
early_cpu_init
setup_arch
_printk
start_kernel
x86_64_start_reservations
x86_64_start_kernel
common_startup_64
because the kernel is booted in a guest.
In order to avoid it, this MSR access needs to be prevented when running
virtualized. That is usually done by checking X86_FEATURE_HYPERVISOR but
for this particular case it is too early yet.
The platform ID needs to be read as early as when microcode is loaded on
the BSP:
load_ucode_bsp ... -> get_microcode_blob ... -> intel_find_matching_signature
and by that time, CPUID leafs haven't been parsed yet.
The microcode loader already has logic to check early whether the kernel
is running virtualized so make that globally available to arch/x86/. The
query whether running virtualized is getting more and more prominent in
recent times so might as well make it an arch-global var which the rest
of the code can use.
Fixes: d8630b67ca ("x86/cpu: Add platform ID to CPU info structure")
Reported-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Tested-by: Binbin Wu <binbin.wu@linux.intel.com>
Link: https://lore.kernel.org/all/20260430020953.1405535-1-binbin.wu@linux.intel.com
Modify all CPUID call sites which implicitly include any of the CPUID
headers to explicitly include them instead.
For KVM's reverse_cpuid.h, just include <asm/cpuid/types.h> since it
references the CPUID_EAX..EDX symbols without using the CPUID APIs.
Note, this allows removing the inclusion of <asm/cpuid/api.h> from within
<asm/processor.h> next. That allows the CPUID API headers to include
<asm/processor.h> without introducing a circular dependency.
Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/20260327021645.555257-1-darwi@linutronix.de
This was done entirely with mindless brute force, using
git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'
to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.
Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.
For the same reason the 'flex' versions will be done as a separate
conversion.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <kees@kernel.org>
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
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
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
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
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>
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>
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
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