6.6-stable review patch. If anyone has any objections, please let me know.
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From: "Borislav Petkov (AMD)" bp@alien8.de
commit 1d81d85d1a19e50d5237dc67d6b825c34ae13de8 upstream
This function should've been split a long time ago because it is used in two paths:
1) On the late loading path, when the microcode is loaded through the request_firmware interface
2) In the save_microcode_in_initrd() path which collects all the microcode patches which are relevant for the current system before the initrd with the microcode container has been jettisoned.
In that path, it is not really necessary to iterate over the nodes on a system and match a patch however it didn't cause any trouble so it was left for a later cleanup
However, that later cleanup was expedited by the fact that Jens was enabling "Use L3 as a NUMA node" in the BIOS setting in his machine and so this causes the NUMA CPU masks used in cpumask_of_node() to be generated *after* 2) above happened on the first node. Which means, all those masks were funky, wrong, uninitialized and whatnot, leading to explosions when dereffing c->microcode in load_microcode_amd().
So split that function and do only the necessary work needed at each stage.
Fixes: 94838d230a6c ("x86/microcode/AMD: Use the family,model,stepping encoded in the patch ID") Reported-by: Jens Axboe axboe@kernel.dk Signed-off-by: Borislav Petkov (AMD) bp@alien8.de Tested-by: Jens Axboe axboe@kernel.dk Link: https://lore.kernel.org/r/91194406-3fdf-4e38-9838-d334af538f74@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/x86/kernel/cpu/microcode/amd.c | 25 +++++++++++++++++-------- 1 file changed, 17 insertions(+), 8 deletions(-)
--- a/arch/x86/kernel/cpu/microcode/amd.c +++ b/arch/x86/kernel/cpu/microcode/amd.c @@ -586,7 +586,7 @@ void __init load_ucode_amd_bsp(struct ea native_rdmsr(MSR_AMD64_PATCH_LEVEL, ed->new_rev, dummy); }
-static enum ucode_state load_microcode_amd(u8 family, const u8 *data, size_t size); +static enum ucode_state _load_microcode_amd(u8 family, const u8 *data, size_t size);
static int __init save_microcode_in_initrd(void) { @@ -607,7 +607,7 @@ static int __init save_microcode_in_init if (!desc.mc) return -EINVAL;
- ret = load_microcode_amd(x86_family(cpuid_1_eax), desc.data, desc.size); + ret = _load_microcode_amd(x86_family(cpuid_1_eax), desc.data, desc.size); if (ret > UCODE_UPDATED) return -EINVAL;
@@ -956,21 +956,30 @@ static enum ucode_state __load_microcode return UCODE_OK; }
-static enum ucode_state load_microcode_amd(u8 family, const u8 *data, size_t size) +static enum ucode_state _load_microcode_amd(u8 family, const u8 *data, size_t size) { - struct cpuinfo_x86 *c; - unsigned int nid, cpu; - struct ucode_patch *p; enum ucode_state ret;
/* free old equiv table */ free_equiv_cpu_table();
ret = __load_microcode_amd(family, data, size); - if (ret != UCODE_OK) { + if (ret != UCODE_OK) cleanup(); + + return ret; +} + +static enum ucode_state load_microcode_amd(u8 family, const u8 *data, size_t size) +{ + struct cpuinfo_x86 *c; + unsigned int nid, cpu; + struct ucode_patch *p; + enum ucode_state ret; + + ret = _load_microcode_amd(family, data, size); + if (ret != UCODE_OK) return ret; - }
for_each_node(nid) { cpu = cpumask_first(cpumask_of_node(nid));