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| author |   Ingo Molnar <mingo@kernel.org> | 2017-06-01 15:52:23 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2017-06-01 15:52:23 +0200 |
| commit | c08d517480ea342cc43acdacc5cf4a795e18151d (patch) | |
| tree | c5cfabb9bf33ddd1336b4d5bb25385d9475cfd8b /arch | |
| parent | x86/debug/32: Convert a smp_processor_id() call to raw to avoid DEBUG_PREEMPT warning (diff) | |
| download | wireguard-linux-c08d517480ea342cc43acdacc5cf4a795e18151d.tar.xz wireguard-linux-c08d517480ea342cc43acdacc5cf4a795e18151d.zip | |
Revert "x86/PAT: Fix Xorg regression on CPUs that don't support PAT"
This reverts commit cbed27cdf0e3f7ea3b2259e86b9e34df02be3fe4.
As Andy Lutomirski observed:
"I think this patch is bogus. pat_enabled() sure looks like it's
supposed to return true if PAT is *enabled*, and these days PAT is
'enabled' even if there's no HW PAT support."
Reported-by: Bernhard Held <berny156@gmx.de>
Reported-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: stable@vger.kernel.org # v4.2+
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/mm/pat.c | 9 |
1 files changed, 3 insertions, 6 deletions
diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c index 83a59a67757a..9b78685b66e6 100644 --- a/arch/x86/mm/pat.c +++ b/arch/x86/mm/pat.c @@ -65,11 +65,9 @@ static int __init nopat(char *str) } early_param("nopat", nopat); -static bool __read_mostly __pat_initialized = false; - bool pat_enabled(void) { - return __pat_initialized; + return !!__pat_enabled; } EXPORT_SYMBOL_GPL(pat_enabled); @@ -227,14 +225,13 @@ static void pat_bsp_init(u64 pat) } wrmsrl(MSR_IA32_CR_PAT, pat); - __pat_initialized = true; __init_cache_modes(pat); } static void pat_ap_init(u64 pat) { - if (!this_cpu_has(X86_FEATURE_PAT)) { + if (!boot_cpu_has(X86_FEATURE_PAT)) { /* * If this happens we are on a secondary CPU, but switched to * PAT on the boot CPU. We have no way to undo PAT. @@ -309,7 +306,7 @@ void pat_init(void) u64 pat; struct cpuinfo_x86 *c = &boot_cpu_data; - if (!__pat_enabled) { + if (!pat_enabled()) { init_cache_modes(); return; } |