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authorLinus Torvalds <torvalds@linux-foundation.org>2019-06-14 06:16:47 -1000
committerLinus Torvalds <torvalds@linux-foundation.org>2019-06-14 06:16:47 -1000
commit72a20cee5d99d231809ee4d3d2c09a96a25451e2 (patch)
tree140c1480236bd8026f2dbcb951ac7f898cccc24f /arch/arm64/kernel/fpsimd.c
parentMerge branch 'akpm' (patches from Andrew) (diff)
parentarm64/sve: Fix missing SVE/FPSIMD endianness conversions (diff)
downloadlinux-dev-72a20cee5d99d231809ee4d3d2c09a96a25451e2.tar.xz
linux-dev-72a20cee5d99d231809ee4d3d2c09a96a25451e2.zip
Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Will Deacon: "Here are some arm64 fixes for -rc5. The only non-trivial change (in terms of the diffstat) is fixing our SVE ptrace API for big-endian machines, but the majority of this is actually the addition of much-needed comments and updates to the documentation to try to avoid this mess biting us again in future. There are still a couple of small things on the horizon, but nothing major at this point. Summary: - Fix broken SVE ptrace API when running in a big-endian configuration - Fix performance regression due to off-by-one in TLBI range checking - Fix build regression when using Clang" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64/sve: Fix missing SVE/FPSIMD endianness conversions arm64: tlbflush: Ensure start/end of address range are aligned to stride arm64: Don't unconditionally add -Wno-psabi to KBUILD_CFLAGS
Diffstat (limited to 'arch/arm64/kernel/fpsimd.c')
-rw-r--r--arch/arm64/kernel/fpsimd.c42
1 files changed, 33 insertions, 9 deletions
diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c
index a38bf74bcca8..bb42cd04baec 100644
--- a/arch/arm64/kernel/fpsimd.c
+++ b/arch/arm64/kernel/fpsimd.c
@@ -39,6 +39,7 @@
#include <linux/slab.h>
#include <linux/stddef.h>
#include <linux/sysctl.h>
+#include <linux/swab.h>
#include <asm/esr.h>
#include <asm/fpsimd.h>
@@ -352,6 +353,23 @@ static int __init sve_sysctl_init(void) { return 0; }
#define ZREG(sve_state, vq, n) ((char *)(sve_state) + \
(SVE_SIG_ZREG_OFFSET(vq, n) - SVE_SIG_REGS_OFFSET))
+#ifdef CONFIG_CPU_BIG_ENDIAN
+static __uint128_t arm64_cpu_to_le128(__uint128_t x)
+{
+ u64 a = swab64(x);
+ u64 b = swab64(x >> 64);
+
+ return ((__uint128_t)a << 64) | b;
+}
+#else
+static __uint128_t arm64_cpu_to_le128(__uint128_t x)
+{
+ return x;
+}
+#endif
+
+#define arm64_le128_to_cpu(x) arm64_cpu_to_le128(x)
+
/*
* Transfer the FPSIMD state in task->thread.uw.fpsimd_state to
* task->thread.sve_state.
@@ -369,14 +387,16 @@ static void fpsimd_to_sve(struct task_struct *task)
void *sst = task->thread.sve_state;
struct user_fpsimd_state const *fst = &task->thread.uw.fpsimd_state;
unsigned int i;
+ __uint128_t *p;
if (!system_supports_sve())
return;
vq = sve_vq_from_vl(task->thread.sve_vl);
- for (i = 0; i < 32; ++i)
- memcpy(ZREG(sst, vq, i), &fst->vregs[i],
- sizeof(fst->vregs[i]));
+ for (i = 0; i < 32; ++i) {
+ p = (__uint128_t *)ZREG(sst, vq, i);
+ *p = arm64_cpu_to_le128(fst->vregs[i]);
+ }
}
/*
@@ -395,14 +415,16 @@ static void sve_to_fpsimd(struct task_struct *task)
void const *sst = task->thread.sve_state;
struct user_fpsimd_state *fst = &task->thread.uw.fpsimd_state;
unsigned int i;
+ __uint128_t const *p;
if (!system_supports_sve())
return;
vq = sve_vq_from_vl(task->thread.sve_vl);
- for (i = 0; i < 32; ++i)
- memcpy(&fst->vregs[i], ZREG(sst, vq, i),
- sizeof(fst->vregs[i]));
+ for (i = 0; i < 32; ++i) {
+ p = (__uint128_t const *)ZREG(sst, vq, i);
+ fst->vregs[i] = arm64_le128_to_cpu(*p);
+ }
}
#ifdef CONFIG_ARM64_SVE
@@ -491,6 +513,7 @@ void sve_sync_from_fpsimd_zeropad(struct task_struct *task)
void *sst = task->thread.sve_state;
struct user_fpsimd_state const *fst = &task->thread.uw.fpsimd_state;
unsigned int i;
+ __uint128_t *p;
if (!test_tsk_thread_flag(task, TIF_SVE))
return;
@@ -499,9 +522,10 @@ void sve_sync_from_fpsimd_zeropad(struct task_struct *task)
memset(sst, 0, SVE_SIG_REGS_SIZE(vq));
- for (i = 0; i < 32; ++i)
- memcpy(ZREG(sst, vq, i), &fst->vregs[i],
- sizeof(fst->vregs[i]));
+ for (i = 0; i < 32; ++i) {
+ p = (__uint128_t *)ZREG(sst, vq, i);
+ *p = arm64_cpu_to_le128(fst->vregs[i]);
+ }
}
int sve_set_vector_length(struct task_struct *task,