diff options
| author | Huacai Chen <chenhuacai@loongson.cn> | 2025-08-20 22:23:44 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-09-09 19:02:15 +0200 |
| commit | b7c715b1f2db80fcf421e153855e3db1483f1f55 (patch) | |
| tree | b502d8bce2b086696a75fb5f0686cabc3226b35c | |
| parent | 76ff6437b42f9be365632130d5ddd8a93f787257 (diff) | |
LoongArch: Save LBT before FPU in setup_sigcontext()
[ Upstream commit 112ca94f6c3b3e0b2002a240de43c487a33e0234 ]
Now if preemption happens between protected_save_fpu_context() and
protected_save_lbt_context(), FTOP context is lost. Because FTOP is
saved by protected_save_lbt_context() but protected_save_fpu_context()
disables TM before that. So save LBT before FPU in setup_sigcontext()
to avoid this potential risk.
Signed-off-by: Hanlu Li <lihanlu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | arch/loongarch/kernel/signal.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/arch/loongarch/kernel/signal.c b/arch/loongarch/kernel/signal.c index 4740cb5b2388..c9f7ca778364 100644 --- a/arch/loongarch/kernel/signal.c +++ b/arch/loongarch/kernel/signal.c @@ -677,6 +677,11 @@ static int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, for (i = 1; i < 32; i++) err |= __put_user(regs->regs[i], &sc->sc_regs[i]); +#ifdef CONFIG_CPU_HAS_LBT + if (extctx->lbt.addr) + err |= protected_save_lbt_context(extctx); +#endif + if (extctx->lasx.addr) err |= protected_save_lasx_context(extctx); else if (extctx->lsx.addr) @@ -684,11 +689,6 @@ static int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, else if (extctx->fpu.addr) err |= protected_save_fpu_context(extctx); -#ifdef CONFIG_CPU_HAS_LBT - if (extctx->lbt.addr) - err |= protected_save_lbt_context(extctx); -#endif - /* Set the "end" magic */ info = (struct sctx_info *)extctx->end.addr; err |= __put_user(0, &info->magic); |