summaryrefslogtreecommitdiff
path: root/arch/x86/lib/mmx_32.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2021-01-24 09:46:05 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2021-01-24 09:46:05 -0800
commit17b6c49da37f5d57d76bf352d32b0ac498e7c133 (patch)
treef96c29cbb729791c4808f219447bc947ffb7a953 /arch/x86/lib/mmx_32.c
parent14c50a66183856672d822f25dbb73ad26d1e8f11 (diff)
parent6e1239c13953f3c2a76e70031f74ddca9ae57cd3 (diff)
Merge tag 'x86_urgent_for_v5.11_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Borislav Petkov: - Add a new Intel model number for Alder Lake - Differentiate which aspects of the FPU state get saved/restored when the FPU is used in-kernel and fix a boot crash on K7 due to early MXCSR access before CR4.OSFXSR is even set. - A couple of noinstr annotation fixes - Correct die ID setting on AMD for users of topology information which need the correct die ID - A SEV-ES fix to handle string port IO to/from kernel memory properly * tag 'x86_urgent_for_v5.11_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/cpu: Add another Alder Lake CPU to the Intel family x86/mmx: Use KFPU_387 for MMX string operations x86/fpu: Add kernel_fpu_begin_mask() to selectively initialize state x86/topology: Make __max_die_per_package available unconditionally x86: __always_inline __{rd,wr}msr() x86/mce: Remove explicit/superfluous tracing locking/lockdep: Avoid noinstr warning for DEBUG_LOCKDEP locking/lockdep: Cure noinstr fail x86/sev: Fix nonistr violation x86/entry: Fix noinstr fail x86/cpu/amd: Set __max_die_per_package on AMD x86/sev-es: Handle string port IO to kernel memory properly
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 4321fa02e18d..419365c48b2a 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"