tree ec25267a630ca152af3d1a476793e25ebd77d960
parent f60a83df4593c5e03e746ded66d8b436c4ad6e41
author Chang S. Bae <chang.seok.bae@intel.com> 1557309745 -0700
committer Thomas Gleixner <tglx@linutronix.de> 1561196333 +0200

x86/entry/64: Switch CR3 before SWAPGS in paranoid entry

When FSGSBASE is enabled, the GSBASE handling in paranoid entry will need
to retrieve the kernel GSBASE which requires that the kernel page table is
active.

As the CR3 switch to the kernel page tables (PTI is active) does not depend
on kernel GSBASE, move the CR3 switch in front of the GSBASE handling.

Comment the EBX content while at it.

No functional change.

[ tglx: Rewrote changelog and comments ]

Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Link: https://lkml.kernel.org/r/1557309753-24073-11-git-send-email-chang.seok.bae@intel.com