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Revert "x86, ucode-amd: Ensure ucode update on suspend/resume after CPU off/online cycle"

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This reverts commit 9f15226e75583547aaf542c6be4bdac1060dd425.  It's just
wrong, and broke resume for Rafael even on a non-AMD CPU.

As Rafael says:
 "... it causes microcode_init_cpu() to be called during resume even for
  CPUs for which there's no microcode to apply.  That, in turn, results
  in executing request_firmware() (on Intel CPUs at least) which doesn't
  work at this stage of resume (we have device interrupts disabled, I/O
  devices are still suspended and so on).

  If I'm not mistaken, the "if (uci->valid)" logic means "if that CPU is
  known to us" , so before commit 9f15226e755 microcode_resume_cpu() was
  called for all CPUs already in the system during suspend, which was
  the right thing to do.  The commit changed it so that the CPUs without
  microcode to apply are now treated as "unknown", which is not quite
  right.

  The problem this commit attempted to solve has to be handled
  differently."

Bisected-and -requested-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Linus Torvalds 2009-12-23 15:04:53 -08:00
parent 17a3be341e
commit 2f99f5c8f0
1 changed files with 1 additions and 1 deletions
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2
arch/x86/kernel/microcode_core.c
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@ -394,7 +394,7 @@ 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 && uci->mc)
if (uci->valid)
ustate = microcode_resume_cpu(cpu);
else
ustate = microcode_init_cpu(cpu);