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| author | Dave Hansen <dave.hansen@linux.intel.com> | 2023-10-03 01:00:45 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2023-10-03 10:27:12 +0300 |
| commit | 3e32552652917f10c0aa8ac75cdc8f0b8d257dec (patch) | |
| tree | 5c7698bc266d6a5cef714aac871d54765944a543 | |
| parent | fbf6449f84bf5e4ad09f2c09ee70ed7d629b5ff6 (diff) | |
| download | linux-3e32552652917f10c0aa8ac75cdc8f0b8d257dec.tar.xz | |
x86/boot: Move x86_cache_alignment initialization to correct spot
c->x86_cache_alignment is initialized from c->x86_clflush_size.
However, commit fbf6449f84bf moved c->x86_clflush_size initialization
to later in boot without moving the c->x86_cache_alignment assignment:
fbf6449f84bf ("x86/sev-es: Set x86_virt_bits to the correct value straight away, instead of a two-phase approach")
This presumably left c->x86_cache_alignment set to zero for longer
than it should be.
The result was an oops on 32-bit kernels while accessing a pointer
at 0x20. The 0x20 came from accessing a structure member at offset
0x10 (buffer->cpumask) from a ZERO_SIZE_PTR=0x10. kmalloc() can
evidently return ZERO_SIZE_PTR when it's given 0 as its alignment
requirement.
Move the c->x86_cache_alignment initialization to be after
c->x86_clflush_size has an actual value.
Fixes: fbf6449f84bf ("x86/sev-es: Set x86_virt_bits to the correct value straight away, instead of a two-phase approach")
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20231002220045.1014760-1-dave.hansen@linux.intel.com
| -rw-r--r-- | arch/x86/kernel/cpu/common.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 8d7063e4f63c..9c51ad5bbf31 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1141,6 +1141,7 @@ void get_cpu_address_sizes(struct cpuinfo_x86 *c) } } c->x86_cache_bits = c->x86_phys_bits; + c->x86_cache_alignment = c->x86_clflush_size; } static void identify_cpu_without_cpuid(struct cpuinfo_x86 *c) @@ -1594,8 +1595,6 @@ static void __init cpu_parse_early_param(void) */ static void __init early_identify_cpu(struct cpuinfo_x86 *c) { - c->x86_cache_alignment = c->x86_clflush_size; - memset(&c->x86_capability, 0, sizeof(c->x86_capability)); c->extended_cpuid_level = 0; |