42 lines
1.5 KiB
Diff
42 lines
1.5 KiB
Diff
From 63f7c8cd3071ae8436b4e39ef5726408e93d41d6 Mon Sep 17 00:00:00 2001
|
|
Message-Id: <63f7c8cd3071ae8436b4e39ef5726408e93d41d6.1594742966.git.zanussi@kernel.org>
|
|
In-Reply-To: <832f7d97d6b989a5b4860dd2dbec58ad6ad5ab81.1594742966.git.zanussi@kernel.org>
|
|
References: <832f7d97d6b989a5b4860dd2dbec58ad6ad5ab81.1594742966.git.zanussi@kernel.org>
|
|
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
|
|
Date: Tue, 11 Dec 2018 15:10:33 +0100
|
|
Subject: [PATCH 175/329] x86/fpu: Disable preemption around local_bh_disable()
|
|
Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.19/older/patches-4.19.132-rt59.tar.xz
|
|
|
|
__fpu__restore_sig() restores the content of the FPU state in the CPUs
|
|
and in order to avoid concurency it disbles BH. On !RT it also disables
|
|
preemption but on RT we can get preempted in BH.
|
|
|
|
Add preempt_disable() while the FPU state is restored.
|
|
|
|
Cc: stable-rt@vger.kernel.org
|
|
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
|
|
---
|
|
arch/x86/kernel/fpu/signal.c | 2 ++
|
|
1 file changed, 2 insertions(+)
|
|
|
|
diff --git a/arch/x86/kernel/fpu/signal.c b/arch/x86/kernel/fpu/signal.c
|
|
index d99a8ee9e185..5e0274a94133 100644
|
|
--- a/arch/x86/kernel/fpu/signal.c
|
|
+++ b/arch/x86/kernel/fpu/signal.c
|
|
@@ -344,10 +344,12 @@ static int __fpu__restore_sig(void __user *buf, void __user *buf_fx, int size)
|
|
sanitize_restored_xstate(tsk, &env, xfeatures, fx_only);
|
|
}
|
|
|
|
+ preempt_disable();
|
|
local_bh_disable();
|
|
fpu->initialized = 1;
|
|
fpu__restore(fpu);
|
|
local_bh_enable();
|
|
+ preempt_enable();
|
|
|
|
return err;
|
|
} else {
|
|
--
|
|
2.17.1
|
|
|