From 69af56ae56a48a2522aad906c4461c6c7c092737 Mon Sep 17 00:00:00 2001
From: Mark Brown <broonie@kernel.org>
Date: Thu, 3 Aug 2023 19:33:23 +0100
Subject: [PATCH] arm64/fpsimd: Sync and zero pad FPSIMD state for streaming
SVE
We have a function sve_sync_from_fpsimd_zeropad() which is used by the
ptrace code to update the SVE state when the user writes to the the
FPSIMD register set. Currently this checks that the task has SVE
enabled but this will miss updates for tasks which have streaming SVE
enabled if SVE has not been enabled for the thread, also do the
conversion if the task has streaming SVE enabled.
Fixes: e12310a0d30f ("arm64/sme: Implement ptrace support for streaming mode SVE registers")
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230803-arm64-fix-ptrace-ssve-no-sve-v1-3-49df214bfb3e@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
---
arch/arm64/kernel/fpsimd.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c
index bfaa70cb040e5..75c37b1c55aaf 100644
--- a/arch/arm64/kernel/fpsimd.c
+++ b/arch/arm64/kernel/fpsimd.c
@@ -835,7 +835,8 @@ 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;
- if (!test_tsk_thread_flag(task, TIF_SVE))
+ if (!test_tsk_thread_flag(task, TIF_SVE) &&
+ !thread_sm_enabled(&task->thread))
return;
vq = sve_vq_from_vl(thread_get_cur_vl(&task->thread));