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authorJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-11 10:41:07 +0300
committerJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-13 08:17:18 +0300
commite09b41010ba33a20a87472ee821fa407a5b8da36 (patch)
treed10dc367189862e7ca5c592f033dc3726e1df4e3 /kernel/arch/x86/mm/iomap_32.c
parentf93b97fd65072de626c074dbe099a1fff05ce060 (diff)
These changes are the raw update to linux-4.4.6-rt14. Kernel sources
are taken from kernel.org, and rt patch from the rt wiki download page. During the rebasing, the following patch collided: Force tick interrupt and get rid of softirq magic(I70131fb85). Collisions have been removed because its logic was found on the source already. Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769 Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'kernel/arch/x86/mm/iomap_32.c')
-rw-r--r--kernel/arch/x86/mm/iomap_32.c12
1 files changed, 6 insertions, 6 deletions
diff --git a/kernel/arch/x86/mm/iomap_32.c b/kernel/arch/x86/mm/iomap_32.c
index b2ffa5c7d..dd25dd167 100644
--- a/kernel/arch/x86/mm/iomap_32.c
+++ b/kernel/arch/x86/mm/iomap_32.c
@@ -84,13 +84,13 @@ void __iomem *
iomap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot)
{
/*
- * For non-PAT systems, promote PAGE_KERNEL_WC to PAGE_KERNEL_UC_MINUS.
- * PAGE_KERNEL_WC maps to PWT, which translates to uncached if the
- * MTRR is UC or WC. UC_MINUS gets the real intention, of the
- * user, which is "WC if the MTRR is WC, UC if you can't do that."
+ * For non-PAT systems, translate non-WB request to UC- just in
+ * case the caller set the PWT bit to prot directly without using
+ * pgprot_writecombine(). UC- translates to uncached if the MTRR
+ * is UC or WC. UC- gets the real intention, of the user, which is
+ * "WC if the MTRR is WC, UC if you can't do that."
*/
- if (!pat_enabled && pgprot_val(prot) ==
- (__PAGE_KERNEL | cachemode2protval(_PAGE_CACHE_MODE_WC)))
+ if (!pat_enabled() && pgprot2cachemode(prot) != _PAGE_CACHE_MODE_WB)
prot = __pgprot(__PAGE_KERNEL |
cachemode2protval(_PAGE_CACHE_MODE_UC_MINUS));