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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2022-09-27 00:53:38 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-09-27 00:53:38 +0300 |
| commit | a1375562c0a87f0fa2eaf3e8ce15824696d4170a (patch) | |
| tree | c56e40167a7531d26d19433566533b7510a6f9ba /drivers/acpi | |
| parent | 3800a713b6070d4f03fb43613a7b7d536a99b2b7 (diff) | |
| parent | e400ad8b7e6a1b9102123c6240289a811501f7d9 (diff) | |
| download | linux-a1375562c0a87f0fa2eaf3e8ce15824696d4170a.tar.xz | |
Merge tag 'x86_urgent_for_v6.0-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Dave Hansen:
- A performance fix for recent large AMD systems that avoids an ancient
cpu idle hardware workaround
- A new Intel model number. Folks like these upstream as soon as
possible so that each developer doing feature development doesn't
need to carry their own #define
- SGX fixes for a userspace crash and a rare kernel warning
* tag 'x86_urgent_for_v6.0-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
ACPI: processor idle: Practically limit "Dummy wait" workaround to old Intel systems
x86/sgx: Handle VA page allocation failure for EAUG on PF.
x86/sgx: Do not fail on incomplete sanitization on premature stop of ksgxd
x86/cpu: Add CPU model numbers for Meteor Lake
Diffstat (limited to 'drivers/acpi')
| -rw-r--r-- | drivers/acpi/processor_idle.c | 23 |
1 files changed, 20 insertions, 3 deletions
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index 16a1663d02d4..9f40917c49ef 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -531,10 +531,27 @@ static void wait_for_freeze(void) /* No delay is needed if we are in guest */ if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) return; + /* + * Modern (>=Nehalem) Intel systems use ACPI via intel_idle, + * not this code. Assume that any Intel systems using this + * are ancient and may need the dummy wait. This also assumes + * that the motivating chipset issue was Intel-only. + */ + if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL) + return; #endif - /* Dummy wait op - must do something useless after P_LVL2 read - because chipsets cannot guarantee that STPCLK# signal - gets asserted in time to freeze execution properly. */ + /* + * Dummy wait op - must do something useless after P_LVL2 read + * because chipsets cannot guarantee that STPCLK# signal gets + * asserted in time to freeze execution properly + * + * This workaround has been in place since the original ACPI + * implementation was merged, circa 2002. + * + * If a profile is pointing to this instruction, please first + * consider moving your system to a more modern idle + * mechanism. + */ inl(acpi_gbl_FADT.xpm_timer_block.address); } |