diff options
| -rw-r--r-- | arch/x86/mm/pat.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c index edf299c8ff6c..7ac68698406c 100644 --- a/arch/x86/mm/pat.c +++ b/arch/x86/mm/pat.c @@ -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); |