WSL2-Linux-Kernel/arch/x86/platform
Guenter Roeck cf40361ede x86/efi: Load fixmap GDT in efi_call_phys_epilog() before setting %cr3
Commit eeb89e2bb1 ("x86/efi: Load fixmap GDT in efi_call_phys_epilog()")
moved loading the fixmap in efi_call_phys_epilog() after load_cr3() since
it was assumed to be more logical.

Turns out this is incorrect: In efi_call_phys_prolog(), the gdt with its
physical address is loaded first, and when the %cr3 is reloaded in _epilog
from initial_page_table to swapper_pg_dir again the gdt is no longer
mapped.  This results in a triple fault if an interrupt occurs after
load_cr3() and before load_fixmap_gdt(0). Calling load_fixmap_gdt(0) first
restores the execution order prior to commit eeb89e2bb1 and fixes the
problem.

Fixes: eeb89e2bb1 ("x86/efi: Load fixmap GDT in efi_call_phys_epilog()")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: linux-efi@vger.kernel.org
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Joerg Roedel <jroedel@suse.de>
Link: https://lkml.kernel.org/r/1536689892-21538-1-git-send-email-linux@roeck-us.net
2018-09-12 21:53:34 +02:00
..
atom x86/platform/atom: Re-use DEFINE_SHOW_ATTRIBUTE() macro 2018-02-16 10:10:14 +01:00
ce4100
efi x86/efi: Load fixmap GDT in efi_call_phys_epilog() before setting %cr3 2018-09-12 21:53:34 +02:00
geode
goldfish
intel x86/platform/intel/iosf_mbi: Add unlocked PMIC bus access notifier unregister 2017-11-10 13:14:02 +01:00
intel-mid Merge branch 'l1tf-final' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-08-14 09:46:06 -07:00
intel-quark x86/platform/quark: Re-use DEFINE_SHOW_ATTRIBUTE() macro 2018-02-16 10:10:14 +01:00
iris
olpc x86/platform/olpc: Use PTR_ERR_OR_ZERO() 2018-08-02 14:25:40 +02:00
scx200
sfi
ts5500
uv Merge branch 'l1tf-final' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-08-14 09:46:06 -07:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00