linux/arch/arm/vfp
Russell King 42019fc50d ARM: vfp: use __copy_from_user() when restoring VFP state
__get_user_error() is used as a fast accessor to make copying structure
members in the signal handling path as efficient as possible.  However,
with software PAN and the recent Spectre variant 1, the efficiency is
reduced as these are no longer fast accessors.

In the case of software PAN, it has to switch the domain register around
each access, and with Spectre variant 1, it would have to repeat the
access_ok() check for each access.

Use __copy_from_user() rather than __get_user_err() for individual
members when restoring VFP state.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-08-02 17:41:37 +01:00
..
entry.S ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+ 2014-07-18 12:29:04 +01:00
Makefile ARM: vfp: use -mfloat-abi=soft to build vfp 2011-10-01 21:08:55 +02:00
vfp.h ARM: 8629/1: vfp: properly tag assembly function declarations in C code 2016-11-22 11:45:09 +00:00
vfpdouble.c ARM: 8026/1: Fix emulation of multiply accumulate instructions 2014-04-14 23:28:24 +01:00
vfphw.S ARM: 8195/1: vfp: Bounce undefined instructions in vectored mode 2014-11-17 20:53:57 +00:00
vfpinstr.h [ARM] 4583/1: ARMv7: Add VFPv3 support 2008-01-26 14:41:28 +00:00
vfpmodule.c ARM: vfp: use __copy_from_user() when restoring VFP state 2018-08-02 17:41:37 +01:00
vfpsingle.c ARM: convert printk(KERN_* to pr_* 2014-11-21 15:24:50 +00:00