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authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2021-01-25 11:19:46 +0100
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2021-01-25 11:19:46 +0100
commit0f8b29fabacbcf0e617896c7ea832b7ea2ef2406 (patch)
tree0187f2baef24b5d78d94aecc7057356a36c58b5d /arch/x86/lib/mmx_32.c
parente71a8d5cf4b4f274740e31b601216071e2a11afa (diff)
parent6ee1d745b7c9fd573fba142a2efdad76a9f1cb04 (diff)
Merge 5.11-rc5 into tty-next
We need the fixes in here and this resolves a merge issue in drivers/tty/tty_io.c Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/x86/lib/mmx_32.c')
-rw-r--r--arch/x86/lib/mmx_32.c20
1 files changed, 15 insertions, 5 deletions
diff --git a/arch/x86/lib/mmx_32.c b/arch/x86/lib/mmx_32.c
index 4321fa02e18df..419365c48b2ad 100644
--- a/arch/x86/lib/mmx_32.c
+++ b/arch/x86/lib/mmx_32.c
@@ -26,6 +26,16 @@
#include <asm/fpu/api.h>
#include <asm/asm.h>
+/*
+ * Use KFPU_387. MMX instructions are not affected by MXCSR,
+ * but both AMD and Intel documentation states that even integer MMX
+ * operations will result in #MF if an exception is pending in FCW.
+ *
+ * EMMS is not needed afterwards because, after calling kernel_fpu_end(),
+ * any subsequent user of the 387 stack will reinitialize it using
+ * KFPU_387.
+ */
+
void *_mmx_memcpy(void *to, const void *from, size_t len)
{
void *p;
@@ -37,7 +47,7 @@ void *_mmx_memcpy(void *to, const void *from, size_t len)
p = to;
i = len >> 6; /* len/64 */
- kernel_fpu_begin();
+ kernel_fpu_begin_mask(KFPU_387);
__asm__ __volatile__ (
"1: prefetch (%0)\n" /* This set is 28 bytes */
@@ -127,7 +137,7 @@ static void fast_clear_page(void *page)
{
int i;
- kernel_fpu_begin();
+ kernel_fpu_begin_mask(KFPU_387);
__asm__ __volatile__ (
" pxor %%mm0, %%mm0\n" : :
@@ -160,7 +170,7 @@ static void fast_copy_page(void *to, void *from)
{
int i;
- kernel_fpu_begin();
+ kernel_fpu_begin_mask(KFPU_387);
/*
* maybe the prefetch stuff can go before the expensive fnsave...
@@ -247,7 +257,7 @@ static void fast_clear_page(void *page)
{
int i;
- kernel_fpu_begin();
+ kernel_fpu_begin_mask(KFPU_387);
__asm__ __volatile__ (
" pxor %%mm0, %%mm0\n" : :
@@ -282,7 +292,7 @@ static void fast_copy_page(void *to, void *from)
{
int i;
- kernel_fpu_begin();
+ kernel_fpu_begin_mask(KFPU_387);
__asm__ __volatile__ (
"1: prefetch (%0)\n"