linux/arch/x86
Andy Lutomirski 61f01dd941 x86_64, asm: Work around AMD SYSRET SS descriptor attribute issue
AMD CPUs don't reinitialize the SS descriptor on SYSRET, so SYSRET with
SS == 0 results in an invalid usermode state in which SS is apparently
equal to __USER_DS but causes #SS if used.

Work around the issue by setting SS to __KERNEL_DS __switch_to, thus
ensuring that SYSRET never happens with SS set to NULL.

This was exposed by a recent vDSO cleanup.

Fixes: e7d6eefaaa x86/vdso32/syscall.S: Do not load __USER32_DS to %ss
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-26 17:57:38 -07:00
..
boot Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-04-13 13:19:10 -07:00
configs x86/build/defconfig: Enable USB_EHCI_TT_NEWSCHED=y 2015-02-19 02:21:14 +01:00
crypto crypto: x86/sha512_ssse3 - fixup for asm function prototype change 2015-04-24 20:09:01 +08:00
ia32 x86_64, asm: Work around AMD SYSRET SS descriptor attribute issue 2015-04-26 17:57:38 -07:00
include x86_64, asm: Work around AMD SYSRET SS descriptor attribute issue 2015-04-26 17:57:38 -07:00
kernel x86_64, asm: Work around AMD SYSRET SS descriptor attribute issue 2015-04-26 17:57:38 -07:00
kvm Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
lguest Some virtio internal cleanups, a new virtio device "virtio input", and 2015-04-22 10:55:06 -07:00
lib x86: fix special __probe_kernel_write() tail zeroing case 2015-04-24 06:58:27 -07:00
math-emu
mm mm: move memtest under mm 2015-04-14 16:49:06 -07:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2014-12-10 15:48:20 -05:00
oprofile x86/asm/entry: Change all 'user_mode_vm()' calls to 'user_mode()' 2015-03-23 11:14:17 +01:00
pci PCI changes for the v4.1 merge window: 2015-04-13 15:45:47 -07:00
platform TTY/Serial patches for 4.1-rc1 2015-04-21 09:33:10 -07:00
power x86/asm/entry: Rename 'init_tss' to 'cpu_tss' 2015-03-06 08:32:58 +01:00
purgatory Merge branches 'x86-build-for-linus', 'x86-cleanups-for-linus' and 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-12-10 12:35:46 -08:00
realmode Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-02-16 14:58:12 -08:00
syscalls xen: features and fixes for 4.1-rc0 2015-04-16 14:01:03 -05:00
tools x86, build: replace Perl script with Shell script 2015-01-26 13:37:18 -08:00
um Merge branch 'exec_domain_rip_v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc 2015-04-15 13:53:55 -07:00
vdso Merge branch 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-04-13 13:36:45 -07:00
video
xen xen: features and fixes for 4.1-rc0 2015-04-16 14:01:03 -05:00
.gitignore x86/build: Add arch/x86/purgatory/ make generated files to gitignore 2014-10-09 09:29:46 +02:00
Kbuild kexec: create a new config option CONFIG_KEXEC_FILE for new syscall 2014-08-29 16:28:16 -07:00
Kconfig Initial ACPI support for arm64: 2015-04-24 08:23:45 -07:00
Kconfig.cpu
Kconfig.debug x86, intel-mid: remove Intel MID specific serial support 2015-03-07 03:25:18 +01:00
Makefile kbuild: use relative path more to include Makefile 2015-04-02 16:42:08 +02:00
Makefile.um kbuild: use relative path more to include Makefile 2015-04-02 16:42:08 +02:00
Makefile_32.cpu