[PATCH] x86, ucode-amd: Ensure ucode update on suspend/resumeafter CPU off/online cycle
From: Andreas Herrmann
Date: Wed Nov 11 2009 - 14:03:46 EST
When switching a CPU offline/online and then doing suspend/resume,
ucode is not updated on this CPU.
This is due to the microcode_fini_cpu() call which frees uci->mc
when setting the CPU offline:
static void microcode_fini_cpu_amd(int cpu)
{
struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
vfree(uci->mc);
uci->mc = NULL;
}
When the CPU is set online uci->mc is still NULL because no ucode
update is required.
Finally this prevents ucode update when resuming after suspend:
static enum ucode_state microcode_resume_cpu(int cpu)
{
struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
if (!uci->mc)
return UCODE_NFOUND;
...
}
Fix is to check whether uci->mc is valid before microcode_resume_cpu()
is called.
Signed-off-by: Andreas Herrmann <andreas.herrmann3@xxxxxxx>
---
arch/x86/kernel/microcode_core.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/arch/x86/kernel/microcode_core.c b/arch/x86/kernel/microcode_core.c
index 230fb09..e68aae3 100644
--- a/arch/x86/kernel/microcode_core.c
+++ b/arch/x86/kernel/microcode_core.c
@@ -391,7 +391,7 @@ static enum ucode_state microcode_update_cpu(int cpu)
struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
enum ucode_state ustate;
- if (uci->valid)
+ if (uci->valid && uci->mc)
ustate = microcode_resume_cpu(cpu);
else
ustate = microcode_init_cpu(cpu);
--
1.6.5.2
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