mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-25 05:34:00 +08:00
x86: Don't rely on VMWare emulating PAT MSR correctly
VMWare seems not to emulate the PAT MSR correctly: reaeding MSR_IA32_CR_PAT returns 0 even after writing another value to it. Commitbd809af16e
triggers this VMWare bug when the kernel is booted as a VMWare guest. Detect this bug and don't use the read value if it is 0. Fixes:bd809af16e
"x86: Enable PAT to use cache mode translation tables" Reported-and-tested-by: Jongman Heo <jongman.heo@samsung.com> Acked-by: Alok N Kataria <akataria@vmware.com> Signed-off-by: Juergen Gross <jgross@suse.com> Link: http://lkml.kernel.org/r/1421039745-14335-1-git-send-email-jgross@suse.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
parent
4a0d3107d6
commit
9d34cfdf47
@ -234,8 +234,13 @@ void pat_init(void)
|
||||
PAT(4, WB) | PAT(5, WC) | PAT(6, UC_MINUS) | PAT(7, UC);
|
||||
|
||||
/* Boot CPU check */
|
||||
if (!boot_pat_state)
|
||||
if (!boot_pat_state) {
|
||||
rdmsrl(MSR_IA32_CR_PAT, boot_pat_state);
|
||||
if (!boot_pat_state) {
|
||||
pat_disable("PAT read returns always zero, disabled.");
|
||||
return;
|
||||
}
|
||||
}
|
||||
|
||||
wrmsrl(MSR_IA32_CR_PAT, pat);
|
||||
|
||||
|
Loading…
Reference in New Issue
Block a user