ARM: 7308/1: vfp: flush thread hwstate before copying ptrace registers
commita4e4a6ee0cc6e069926d006b7a6efd73d33edfcc
authorWill Deacon <will.deacon@arm.com>
Mon, 30 Jan 2012 19:23:29 +0000 (30 20:23 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Mon, 13 Feb 2012 19:16:52 +0000 (13 11:16 -0800)
tree53d9f6c03eec51809123d3cbb48de9432fcd5bc5
parentc85ca4cdfafaee9fd428b934fea18e5c2d850fb6
ARM: 7308/1: vfp: flush thread hwstate before copying ptrace registers

commit 8130b9d7b9d858aa04ce67805e8951e3cb6e9b2f upstream.

If we are context switched whilst copying into a thread's
vfp_hard_struct then the partial copy may be corrupted by the VFP
context switching code (see "ARM: vfp: flush thread hwstate before
restoring context from sigframe").

This patch updates the ptrace VFP set code so that the thread state is
flushed before the copy, therefore disabling VFP and preventing
corruption from occurring.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/arm/kernel/ptrace.c