Commit-ID: ad025a73f0e9344ac73ffe1b74c184033e08e7d5 Gitweb: http://git.kernel.org/tip/ad025a73f0e9344ac73ffe1b74c184033e08e7d5 Author: Toshi Kani <toshi.k...@hpe.com> AuthorDate: Wed, 23 Mar 2016 15:42:01 -0600 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Tue, 29 Mar 2016 12:23:26 +0200
x86/mtrr: Fix PAT init handling when MTRR is disabled get_mtrr_state() calls pat_init() on BSP even if MTRR is disabled. This results in calling pat_init() on BSP only since APs do not call pat_init() when MTRR is disabled. This inconsistency between BSP and APs leads to undefined behavior. Make BSP's calling condition to pat_init() consistent with AP's, mtrr_ap_init() and mtrr_aps_init(). Signed-off-by: Toshi Kani <toshi.k...@hpe.com> Reviewed-by: Thomas Gleixner <t...@linutronix.de> Cc: Andrew Morton <a...@linux-foundation.org> Cc: Andy Lutomirski <l...@amacapital.net> Cc: Borislav Petkov <b...@alien8.de> Cc: Borislav Petkov <b...@suse.de> Cc: Brian Gerst <brge...@gmail.com> Cc: Denys Vlasenko <dvlas...@redhat.com> Cc: H. Peter Anvin <h...@zytor.com> Cc: Juergen Gross <jgr...@suse.com> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Luis R. Rodriguez <mcg...@suse.com> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Toshi Kani <toshi.k...@hp.com> Cc: elli...@hpe.com Cc: konrad.w...@oracle.com Cc: paul.gortma...@windriver.com Cc: xen-de...@lists.xenproject.org Link: http://lkml.kernel.org/r/1458769323-24491-6-git-send-email-toshi.k...@hpe.com Signed-off-by: Ingo Molnar <mi...@kernel.org> --- arch/x86/kernel/cpu/mtrr/generic.c | 24 ++++++++++++++---------- arch/x86/kernel/cpu/mtrr/main.c | 3 +++ arch/x86/kernel/cpu/mtrr/mtrr.h | 1 + 3 files changed, 18 insertions(+), 10 deletions(-) diff --git a/arch/x86/kernel/cpu/mtrr/generic.c b/arch/x86/kernel/cpu/mtrr/generic.c index 19f5736..8d7a29e 100644 --- a/arch/x86/kernel/cpu/mtrr/generic.c +++ b/arch/x86/kernel/cpu/mtrr/generic.c @@ -444,11 +444,24 @@ static void __init print_mtrr_state(void) pr_debug("TOM2: %016llx aka %lldM\n", mtrr_tom2, mtrr_tom2>>20); } +/* PAT setup for BP. We need to go through sync steps here */ +void __init mtrr_bp_pat_init(void) +{ + unsigned long flags; + + local_irq_save(flags); + prepare_set(); + + pat_init(); + + post_set(); + local_irq_restore(flags); +} + /* Grab all of the MTRR state for this CPU into *state */ bool __init get_mtrr_state(void) { struct mtrr_var_range *vrs; - unsigned long flags; unsigned lo, dummy; unsigned int i; @@ -481,15 +494,6 @@ bool __init get_mtrr_state(void) mtrr_state_set = 1; - /* PAT setup for BP. We need to go through sync steps here */ - local_irq_save(flags); - prepare_set(); - - pat_init(); - - post_set(); - local_irq_restore(flags); - return !!(mtrr_state.enabled & MTRR_STATE_MTRR_ENABLED); } diff --git a/arch/x86/kernel/cpu/mtrr/main.c b/arch/x86/kernel/cpu/mtrr/main.c index 8b1947b..7d393ec 100644 --- a/arch/x86/kernel/cpu/mtrr/main.c +++ b/arch/x86/kernel/cpu/mtrr/main.c @@ -752,6 +752,9 @@ void __init mtrr_bp_init(void) /* BIOS may override */ __mtrr_enabled = get_mtrr_state(); + if (mtrr_enabled()) + mtrr_bp_pat_init(); + if (mtrr_cleanup(phys_addr)) { changed_by_mtrr_cleanup = 1; mtrr_if->set_all(); diff --git a/arch/x86/kernel/cpu/mtrr/mtrr.h b/arch/x86/kernel/cpu/mtrr/mtrr.h index 951884d..6c7ced0 100644 --- a/arch/x86/kernel/cpu/mtrr/mtrr.h +++ b/arch/x86/kernel/cpu/mtrr/mtrr.h @@ -52,6 +52,7 @@ void set_mtrr_prepare_save(struct set_mtrr_context *ctxt); void fill_mtrr_var_range(unsigned int index, u32 base_lo, u32 base_hi, u32 mask_lo, u32 mask_hi); bool get_mtrr_state(void); +void mtrr_bp_pat_init(void); extern void set_mtrr_ops(const struct mtrr_ops *ops);