linux-IllusionX/arch
Juergen Gross def9331a12 x86/amd: don't set X86_BUG_SYSRET_SS_ATTRS when running under Xen
When running as Xen pv guest X86_BUG_SYSRET_SS_ATTRS must not be set
on AMD cpus.

This bug/feature bit is kind of special as it will be used very early
when switching threads. Setting the bit and clearing it a little bit
later leaves a critical window where things can go wrong. This time
window has enlarged a little bit by using setup_clear_cpu_cap() instead
of the hypervisor's set_cpu_features callback. It seems this larger
window now makes it rather easy to hit the problem.

The proper solution is to never set the bit in case of Xen.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Juergen Gross <jgross@suse.com>
2017-05-11 15:55:14 +02:00
..
alpha
arc
arm xen: Implement EFI reset_system callback 2017-05-02 12:06:50 +02:00
arm64 xen/arm,arm64: fix xen_dma_ops after 815dd18 "Consolidate get_dma_ops..." 2017-05-02 11:14:42 +02:00
blackfin
c6x
cris
frv
h8300
hexagon
ia64
m32r
m68k
metag
microblaze
mips
mn10300
nios2
openrisc
parisc
powerpc Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-05-01 23:54:56 -07:00
s390 Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-05-01 23:54:56 -07:00
score
sh
sparc
tile
um Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-05-01 23:54:56 -07:00
unicore32 Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-05-01 23:54:56 -07:00
x86 x86/amd: don't set X86_BUG_SYSRET_SS_ATTRS when running under Xen 2017-05-11 15:55:14 +02:00
xtensa
.gitignore
Kconfig