From: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
commit c9d66999f064947e6b577ceacc1eb2fbca6a8d3c upstream.
When fp/simd is not supported on the system, fail the operations
of FP/SIMD regsets.
Fixes: 82e0191a1aa11abf ("arm64: Support systems without FP/ASIMD")
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Reviewed-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
Reviewed-by: Catalin Marinas <catalin.marinas@xxxxxxx>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
Signed-off-by: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/arm64/kernel/ptrace.c | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)
--- a/arch/arm64/kernel/ptrace.c
+++ b/arch/arm64/kernel/ptrace.c
@@ -627,6 +627,13 @@ static int gpr_set(struct task_struct *t
return 0;
}
+static int fpr_active(struct task_struct *target, const struct user_regset *regset)
+{
+ if (!system_supports_fpsimd())
+ return -ENODEV;
+ return regset->n;
+}
+
/*
* TODO: update fp accessors for lazy context switching (sync/flush hwstate)
*/
@@ -649,6 +656,9 @@ static int fpr_get(struct task_struct *t
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
+ if (!system_supports_fpsimd())
+ return -EINVAL;
+
if (target == current)
fpsimd_preserve_current_state();
@@ -688,6 +698,9 @@ static int fpr_set(struct task_struct *t
{
int ret;
+ if (!system_supports_fpsimd())
+ return -EINVAL;
+
ret = __fpr_set(target, regset, pos, count, kbuf, ubuf, 0);
if (ret)
return ret;
@@ -990,6 +1003,7 @@ static const struct user_regset aarch64_
*/
.size = sizeof(u32),
.align = sizeof(u32),
+ .active = fpr_active,
.get = fpr_get,
.set = fpr_set
},
@@ -1176,6 +1190,9 @@ static int compat_vfp_get(struct task_st
compat_ulong_t fpscr;
int ret, vregs_end_pos;
+ if (!system_supports_fpsimd())
+ return -EINVAL;
+
uregs = &target->thread.uw.fpsimd_state;
if (target == current)
@@ -1209,6 +1226,9 @@ static int compat_vfp_set(struct task_st
compat_ulong_t fpscr;
int ret, vregs_end_pos;
+ if (!system_supports_fpsimd())
+ return -EINVAL;
+
uregs = &target->thread.uw.fpsimd_state;
vregs_end_pos = VFP_STATE_SIZE - sizeof(compat_ulong_t);
@@ -1266,6 +1286,7 @@ static const struct user_regset aarch32_
.n = VFP_STATE_SIZE / sizeof(compat_ulong_t),
.size = sizeof(compat_ulong_t),
.align = sizeof(compat_ulong_t),
+ .active = fpr_active,
.get = compat_vfp_get,
.set = compat_vfp_set
},
