From: tip-bot for Borislav Petkov <tipbot@zytor.com>
To: linux-tip-commits@vger.kernel.org
Cc: toshi.kani@hp.com, hpa@zytor.com, mcgrof@suse.com,
linux-kernel@vger.kernel.org, akpm@linux-foundation.org,
linux-mm@kvack.org, luto@amacapital.net, tglx@linutronix.de,
bp@suse.de, mingo@kernel.org, torvalds@linux-foundation.org,
peterz@infradead.org
Subject: [tip:x86/mm] x86/mm/pat: Untangle pat_init()
Date: Sun, 7 Jun 2015 10:39:22 -0700 [thread overview]
Message-ID: <tip-9dac6290945142e6b87d9f027edfee676dcfbfda@git.kernel.org> (raw)
In-Reply-To: <1433436928-31903-2-git-send-email-bp@alien8.de>
Commit-ID: 9dac6290945142e6b87d9f027edfee676dcfbfda
Gitweb: http://git.kernel.org/tip/9dac6290945142e6b87d9f027edfee676dcfbfda
Author: Borislav Petkov <bp@suse.de>
AuthorDate: Thu, 4 Jun 2015 18:55:09 +0200
Committer: Ingo Molnar <mingo@kernel.org>
CommitDate: Sun, 7 Jun 2015 15:28:52 +0200
x86/mm/pat: Untangle pat_init()
Split it into a BSP and AP version which makes the PAT
initialization path actually readable again.
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Toshi Kani <toshi.kani@hp.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Elliott@hp.com
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: arnd@arndb.de
Cc: hch@lst.de
Cc: hmh@hmh.eng.br
Cc: jgross@suse.com
Cc: konrad.wilk@oracle.com
Cc: linux-mm <linux-mm@kvack.org>
Cc: linux-nvdimm@lists.01.org
Cc: stefan.bader@canonical.com
Cc: yigal@plexistor.com
Link: http://lkml.kernel.org/r/1433436928-31903-2-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
arch/x86/mm/pat.c | 69 ++++++++++++++++++++++++++++++++-----------------------
1 file changed, 40 insertions(+), 29 deletions(-)
diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index a1c9654..476d078 100644
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat.c
@@ -36,6 +36,8 @@
#undef pr_fmt
#define pr_fmt(fmt) "" fmt
+static bool boot_cpu_done;
+
static int __read_mostly __pat_enabled = IS_ENABLED(CONFIG_X86_PAT);
static inline void pat_disable(const char *reason)
@@ -194,31 +196,47 @@ void pat_init_cache_modes(void)
#define PAT(x, y) ((u64)PAT_ ## y << ((x)*8))
-void pat_init(void)
+static void pat_bsp_init(u64 pat)
{
- u64 pat;
- bool boot_cpu = !boot_pat_state;
+ if (!cpu_has_pat) {
+ pat_disable("PAT not supported by CPU.");
+ return;
+ }
- if (!pat_enabled())
+ rdmsrl(MSR_IA32_CR_PAT, boot_pat_state);
+ if (!boot_pat_state) {
+ pat_disable("PAT MSR is 0, disabled.");
return;
+ }
+ wrmsrl(MSR_IA32_CR_PAT, pat);
+
+ pat_init_cache_modes();
+}
+
+static void pat_ap_init(u64 pat)
+{
if (!cpu_has_pat) {
- if (!boot_pat_state) {
- pat_disable("PAT not supported by CPU.");
- return;
- } else {
- /*
- * If this happens we are on a secondary CPU, but
- * switched to PAT on the boot CPU. We have no way to
- * undo PAT.
- */
- pr_err("x86/PAT: PAT enabled, but not supported by secondary CPU\n");
- BUG();
- }
+ /*
+ * If this happens we are on a secondary CPU, but switched to
+ * PAT on the boot CPU. We have no way to undo PAT.
+ */
+ panic("x86/PAT: PAT enabled, but not supported by secondary CPU\n");
}
- /* Set PWT to Write-Combining. All other bits stay the same */
+ wrmsrl(MSR_IA32_CR_PAT, pat);
+}
+
+void pat_init(void)
+{
+ u64 pat;
+
+ if (!pat_enabled())
+ return;
+
/*
+ * Set PWT to Write-Combining. All other bits stay the same:
+ *
* PTE encoding used in Linux:
* PAT
* |PCD
@@ -233,19 +251,12 @@ void pat_init(void)
pat = PAT(0, WB) | PAT(1, WC) | PAT(2, UC_MINUS) | PAT(3, UC) |
PAT(4, WB) | PAT(5, WC) | PAT(6, UC_MINUS) | PAT(7, UC);
- /* Boot CPU check */
- 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;
- }
+ if (!boot_cpu_done) {
+ pat_bsp_init(pat);
+ boot_cpu_done = true;
+ } else {
+ pat_ap_init(pat);
}
-
- wrmsrl(MSR_IA32_CR_PAT, pat);
-
- if (boot_cpu)
- pat_init_cache_modes();
}
#undef PAT
next prev parent reply other threads:[~2015-06-07 17:40 UTC|newest]
Thread overview: 40+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-06-04 16:55 [PATCH 00/20] tip queue 2015-06-04 Borislav Petkov
2015-06-04 16:55 ` [PATCH 01/20] x86/mm/pat: Untangle pat_init() Borislav Petkov
2015-06-07 17:39 ` tip-bot for Borislav Petkov [this message]
2015-06-04 16:55 ` [PATCH 02/20] x86/mm/pat: Emulate PAT when it is disabled Borislav Petkov
2015-06-07 17:39 ` [tip:x86/mm] " tip-bot for Borislav Petkov
2015-06-04 16:55 ` [PATCH 03/20] x86/mm/pat: Remove pat_enabled() checks Borislav Petkov
2015-06-07 17:40 ` [tip:x86/mm] " tip-bot for Borislav Petkov
2015-06-04 16:55 ` [PATCH 04/20] x86/mm/pat: Use 7th PAT MSR slot for Write-Through PAT type Borislav Petkov
2015-06-04 16:55 ` [PATCH 05/20] x86/mm/pat: Change reserve_memtype() for Write-Through type Borislav Petkov
2015-06-07 17:40 ` [tip:x86/mm] " tip-bot for Toshi Kani
2015-06-04 16:55 ` [PATCH 06/20] x86/mm: Teach is_new_memtype_allowed() about " Borislav Petkov
2015-06-07 17:41 ` [tip:x86/mm] " tip-bot for Toshi Kani
2015-06-04 16:55 ` [PATCH 07/20] x86/mm, asm-generic: Add ioremap_wt() for creating Write-Through mappings Borislav Petkov
2015-06-07 17:41 ` [tip:x86/mm] " tip-bot for Toshi Kani
2015-06-04 16:55 ` [PATCH 08/20] arch/*/io.h: Add ioremap_wt() to all architectures Borislav Petkov
2015-06-07 17:41 ` [tip:x86/mm] " tip-bot for Toshi Kani
2015-06-04 16:55 ` [PATCH 09/20] video/fbdev, asm/io.h: Remove ioremap_writethrough() Borislav Petkov
2015-06-07 17:41 ` [tip:x86/mm] " tip-bot for Toshi Kani
2015-06-04 16:55 ` [PATCH 10/20] x86/mm/pat: Add pgprot_writethrough() Borislav Petkov
2015-06-07 17:42 ` [tip:x86/mm] " tip-bot for Toshi Kani
2015-06-04 16:55 ` [PATCH 11/20] x86/mm/pat: Extend set_page_memtype() to support Write-Through type Borislav Petkov
2015-06-07 17:42 ` [tip:x86/mm] " tip-bot for Toshi Kani
2015-06-04 16:55 ` [PATCH 12/20] x86/mm: Add set_memory_wt() for " Borislav Petkov
2015-06-07 17:42 ` [tip:x86/mm] x86/mm/pat: " tip-bot for Toshi Kani
2015-06-04 16:55 ` [PATCH 13/20] drivers/block/pmem: Map NVDIMM in Write-Through mode Borislav Petkov
2015-06-07 17:43 ` [tip:x86/mm] " tip-bot for Toshi Kani
2015-06-04 16:55 ` [PATCH 14/20] x86/mce: Add Local MCE definitions Borislav Petkov
2015-06-07 17:43 ` [tip:x86/core] " tip-bot for Ashok Raj
2015-06-04 16:55 ` [PATCH 15/20] x86/mce: Add infrastructure to support Local MCE Borislav Petkov
2015-06-07 17:43 ` [tip:x86/core] " tip-bot for Ashok Raj
2015-06-04 16:55 ` [PATCH 16/20] x86/mce: Handle Local MCE events Borislav Petkov
2015-06-07 17:44 ` [tip:x86/core] " tip-bot for Ashok Raj
2015-06-04 16:55 ` [PATCH 17/20] x86: Kill CONFIG_X86_HT Borislav Petkov
2015-06-07 17:44 ` [tip:x86/core] " tip-bot for Borislav Petkov
2015-06-04 16:55 ` [PATCH 18/20] x86/uapi: Do not export <asm/msr-index.h> as part of the user API headers Borislav Petkov
2015-06-07 17:44 ` [tip:x86/core] " tip-bot for Borislav Petkov
2015-06-04 16:55 ` [PATCH 19/20] x86/microcode: Disable builtin microcode loading on 32-bit for now Borislav Petkov
2015-06-07 17:45 ` [tip:x86/microcode] " tip-bot for Borislav Petkov
2015-06-04 16:55 ` [PATCH 20/20] x86/microcode: Correct variables type Borislav Petkov
2015-06-07 17:45 ` [tip:x86/microcode] x86/microcode: Correct CPU family related variable types tip-bot for Andy Shevchenko
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