linux_dsm_epyc7002/arch
Chen Yu 1a371e67dc x86/microcode/intel: Check patch signature before saving microcode for early loading
Currently, scan_microcode() leverages microcode_matches() to check
if the microcode matches the CPU by comparing the family and model.
However, the processor stepping and flags of the microcode signature
should also be considered when saving a microcode patch for early
update.

Use find_matching_signature() in scan_microcode() and get rid of the
now-unused microcode_matches() which is a good cleanup in itself.

Complete the verification of the patch being saved for early loading in
save_microcode_patch() directly. This needs to be done there too because
save_mc_for_early() will call save_microcode_patch() too.

The second reason why this needs to be done is because the loader still
tries to support, at least hypothetically, mixed-steppings systems and
thus adds all patches to the cache that belong to the same CPU model
albeit with different steppings.

For example:

  microcode: CPU: sig=0x906ec, pf=0x2, rev=0xd6
  microcode: mc_saved[0]: sig=0x906e9, pf=0x2a, rev=0xd6, total size=0x19400, date = 2020-04-23
  microcode: mc_saved[1]: sig=0x906ea, pf=0x22, rev=0xd6, total size=0x19000, date = 2020-04-27
  microcode: mc_saved[2]: sig=0x906eb, pf=0x2, rev=0xd6, total size=0x19400, date = 2020-04-23
  microcode: mc_saved[3]: sig=0x906ec, pf=0x22, rev=0xd6, total size=0x19000, date = 2020-04-27
  microcode: mc_saved[4]: sig=0x906ed, pf=0x22, rev=0xd6, total size=0x19400, date = 2020-04-23

The patch which is being saved for early loading, however, can only be
the one which fits the CPU this runs on so do the signature verification
before saving.

 [ bp: Do signature verification in save_microcode_patch()
       and rewrite commit message. ]

Fixes: ec400ddeff ("x86/microcode_intel_early.c: Early update ucode on Intel's CPU")
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: stable@vger.kernel.org
Link: https://bugzilla.kernel.org/show_bug.cgi?id=208535
Link: https://lkml.kernel.org/r/20201113015923.13960-1-yu.c.chen@intel.com
2020-11-17 10:33:18 +01:00
..
alpha arch-cleanup-2020-10-22 2020-10-23 10:06:38 -07:00
arc ARC: [plat-hsdk] Remap CCMs super early in asm boot trampoline 2020-11-02 11:45:09 -08:00
arm A set of fixes for perf: 2020-11-15 09:46:36 -08:00
arm64 Fixes for ARM and x86, the latter especially for old processors 2020-11-15 09:57:58 -08:00
c6x arch-cleanup-2020-10-22 2020-10-23 10:06:38 -07:00
csky perf/arch: Remove perf_sample_data::regs_user_copy 2020-11-09 18:12:34 +01:00
h8300 arch-cleanup-2020-10-22 2020-10-23 10:06:38 -07:00
hexagon arch-cleanup-2020-10-22 2020-10-23 10:06:38 -07:00
ia64 treewide: Convert macro and uses of __section(foo) to __section("foo") 2020-10-25 14:51:49 -07:00
m68k arch-cleanup-2020-10-22 2020-10-23 10:06:38 -07:00
microblaze treewide: Convert macro and uses of __section(foo) to __section("foo") 2020-10-25 14:51:49 -07:00
mips treewide: Convert macro and uses of __section(foo) to __section("foo") 2020-10-25 14:51:49 -07:00
nds32 arch-cleanup-2020-10-22 2020-10-23 10:06:38 -07:00
nios2 arch-cleanup-2020-10-22 2020-10-23 10:06:38 -07:00
openrisc arch-cleanup-2020-10-22 2020-10-23 10:06:38 -07:00
parisc treewide: Convert macro and uses of __section(foo) to __section("foo") 2020-10-25 14:51:49 -07:00
powerpc A set of fixes for perf: 2020-11-15 09:46:36 -08:00
riscv A set of fixes for perf: 2020-11-15 09:46:36 -08:00
s390 perf/arch: Remove perf_sample_data::regs_user_copy 2020-11-09 18:12:34 +01:00
sh treewide: Convert macro and uses of __section(foo) to __section("foo") 2020-10-25 14:51:49 -07:00
sparc treewide: Convert macro and uses of __section(foo) to __section("foo") 2020-10-25 14:51:49 -07:00
um um: Call pgtable_pmd_page_dtor() in __pmd_free_tlb() 2020-11-10 21:49:32 +01:00
x86 x86/microcode/intel: Check patch signature before saving microcode for early loading 2020-11-17 10:33:18 +01:00
xtensa ARM, xtensa: highmem: avoid clobbering non-page aligned memory reservations 2020-11-04 10:42:57 +02:00
.gitignore
Kconfig Merge branch 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-10-22 09:59:21 -07:00