| Message ID | E1b7oBz-0005wE-1t@rmk-PC.armlinux.org.uk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, May 31, 2016 at 07:15:03PM +0100, Russell King wrote: > PTRACE_SETVFPREGS fails to properly mark the VFP register set to be > reloaded, because it undoes one of the effects of vfp_flush_hwstate(). > > Specifically vfp_flush_hwstate() sets thread->vfpstate.hard.cpu to > an invalid CPU number, but vfp_set() overwrites this with the original > CPU number, thereby rendering the hardware state as apparently "valid", > even though the software state is more recent. > > Fix this by reverting the previous change. > > Cc: <stable@vger.kernel.org> > Fixes: 8130b9d7b9d8 ("ARM: 7308/1: vfp: flush thread hwstate before copying ptrace registers") > Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> > --- > Will, please ack this. Acked-by: Will Deacon <will.deacon@arm.com> Will > > arch/arm/kernel/ptrace.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c > index ef9119f7462e..4d9375814b53 100644 > --- a/arch/arm/kernel/ptrace.c > +++ b/arch/arm/kernel/ptrace.c > @@ -733,8 +733,8 @@ static int vfp_set(struct task_struct *target, > if (ret) > return ret; > > - vfp_flush_hwstate(thread); > thread->vfpstate.hard = new_vfp; > + vfp_flush_hwstate(thread); > > return 0; > } > -- > 2.1.0 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel >
diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c index ef9119f7462e..4d9375814b53 100644 --- a/arch/arm/kernel/ptrace.c +++ b/arch/arm/kernel/ptrace.c @@ -733,8 +733,8 @@ static int vfp_set(struct task_struct *target, if (ret) return ret; - vfp_flush_hwstate(thread); thread->vfpstate.hard = new_vfp; + vfp_flush_hwstate(thread); return 0; }
PTRACE_SETVFPREGS fails to properly mark the VFP register set to be reloaded, because it undoes one of the effects of vfp_flush_hwstate(). Specifically vfp_flush_hwstate() sets thread->vfpstate.hard.cpu to an invalid CPU number, but vfp_set() overwrites this with the original CPU number, thereby rendering the hardware state as apparently "valid", even though the software state is more recent. Fix this by reverting the previous change. Cc: <stable@vger.kernel.org> Fixes: 8130b9d7b9d8 ("ARM: 7308/1: vfp: flush thread hwstate before copying ptrace registers") Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> --- Will, please ack this. arch/arm/kernel/ptrace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)