diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2008-01-30 13:34:08 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-01-30 13:34:08 +0100 |
| commit | cd8ddf1a2800026dd58433333cce7a65cbc6c6d2 (patch) | |
| tree | 4f741ddde5efa85299e900a24a71f893fc7ed34d | |
| parent | af1e6844d60057774910a2d08bd75b67d73ba7d5 (diff) | |
x86: clflush_page_range needs mfence
clflush is an unordered operation with respect to other memory
traffic, including other CLFLUSH instructions. This needs proper
fencing with mfence.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
| -rw-r--r-- | arch/x86/mm/pageattr.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index cdd2ea2a223..90b658ac39c 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -25,12 +25,24 @@ within(unsigned long addr, unsigned long start, unsigned long end) /* * Flushing functions */ + + +/** + * clflush_cache_range - flush a cache range with clflush + * @addr: virtual start address + * @size: number of bytes to flush + * + * clflush is an unordered instruction which needs fencing with mfence + * to avoid ordering issues. + */ void clflush_cache_range(void *addr, int size) { int i; + mb(); for (i = 0; i < size; i += boot_cpu_data.x86_clflush_size) clflush(addr+i); + mb(); } static void __cpa_flush_all(void *arg) |