From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org, Toshi Kani <toshi.kani@hpe.com>,
Thomas Gleixner <tglx@linutronix.de>,
Andrew Morton <akpm@linux-foundation.org>,
Andy Lutomirski <luto@amacapital.net>,
Borislav Petkov <bp@alien8.de>, Borislav Petkov <bp@suse.de>,
Brian Gerst <brgerst@gmail.com>,
Denys Vlasenko <dvlasenk@redhat.com>,
"H. Peter Anvin" <hpa@zytor.com>, Juergen Gross <jgross@suse.com>,
Linus Torvalds <torvalds@linux-foundation.org>,
"Luis R. Rodriguez" <mcgrof@suse.com>,
Peter Zijlstra <peterz@infradead.org>,
Toshi Kani <toshi.kani@hp.com>,
elliott@hpe.com, konrad.wilk@oracle.com,
paul.gortmaker@windriver.com, xen-devel@lists.xenproject.org,
Ingo Molnar <mingo@kernel.org>
Subject: [PATCH 4.6 29/56] x86/pat: Document the PAT initialization sequence
Date: Sun, 14 Aug 2016 22:37:33 +0200 [thread overview]
Message-ID: <20160814202506.132428006@linuxfoundation.org> (raw)
In-Reply-To: <20160814202504.908694181@linuxfoundation.org>
4.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Toshi Kani <toshi.kani@hpe.com>
commit b6350c21cfe8aa9d65e189509a23c0ea4b8362c2 upstream.
Update PAT documentation to describe how PAT is initialized under
various configurations.
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: elliott@hpe.com
Cc: konrad.wilk@oracle.com
Cc: paul.gortmaker@windriver.com
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1458769323-24491-8-git-send-email-toshi.kani@hpe.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
Documentation/x86/pat.txt | 32 ++++++++++++++++++++++++++++++++
1 file changed, 32 insertions(+)
--- a/Documentation/x86/pat.txt
+++ b/Documentation/x86/pat.txt
@@ -196,3 +196,35 @@ Another, more verbose way of getting PAT
"debugpat" boot parameter. With this parameter, various debug messages are
printed to dmesg log.
+PAT Initialization
+------------------
+
+The following table describes how PAT is initialized under various
+configurations. The PAT MSR must be updated by Linux in order to support WC
+and WT attributes. Otherwise, the PAT MSR has the value programmed in it
+by the firmware. Note, Xen enables WC attribute in the PAT MSR for guests.
+
+ MTRR PAT Call Sequence PAT State PAT MSR
+ =========================================================
+ E E MTRR -> PAT init Enabled OS
+ E D MTRR -> PAT init Disabled -
+ D E MTRR -> PAT disable Disabled BIOS
+ D D MTRR -> PAT disable Disabled -
+ - np/E PAT -> PAT disable Disabled BIOS
+ - np/D PAT -> PAT disable Disabled -
+ E !P/E MTRR -> PAT init Disabled BIOS
+ D !P/E MTRR -> PAT disable Disabled BIOS
+ !M !P/E MTRR stub -> PAT disable Disabled BIOS
+
+ Legend
+ ------------------------------------------------
+ E Feature enabled in CPU
+ D Feature disabled/unsupported in CPU
+ np "nopat" boot option specified
+ !P CONFIG_X86_PAT option unset
+ !M CONFIG_MTRR option unset
+ Enabled PAT state set to enabled
+ Disabled PAT state set to disabled
+ OS PAT initializes PAT MSR with OS setting
+ BIOS PAT keeps PAT MSR with BIOS setting
+
next prev parent reply other threads:[~2016-08-14 20:44 UTC|newest]
Thread overview: 58+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CGME20160814203815uscas1p2549802c8af27d2aa233de8bce43fe3ee@uscas1p2.samsung.com>
2016-08-14 20:37 ` [PATCH 4.6 00/56] 4.6.7-stable review Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 01/56] libnvdimm, dax: record the specified alignment of a dax-device instance Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 02/56] libnvdimm, pfn, dax: fix initialization vs autodetect for mode + alignment Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 03/56] ppp: defer netns reference release for ppp channel Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 04/56] tcp: make challenge acks less predictable Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 05/56] tcp: enable per-socket rate limiting of all challenge acks Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 06/56] bonding: set carrier off for devices created through netlink Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 07/56] net: bgmac: Fix infinite loop in bgmac_dma_tx_add() Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 08/56] vlan: use a valid default mtu value for vlan over macsec Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 09/56] bridge: Fix incorrect re-injection of LLDP packets Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 10/56] net: ipv6: Always leave anycast and multicast groups on link down Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 11/56] net/irda: fix NULL pointer dereference on memory allocation failure Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 12/56] qed: Fix setting/clearing bit in completion bitmap Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 13/56] macsec: ensure rx_sa is set when validation is disabled Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 14/56] tcp: consider recv buf for the initial window scale Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 16/56] arm: oabi compat: add missing access checks Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 17/56] KEYS: 64-bit MIPS needs to use compat_sys_keyctl for 32-bit userspace Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 18/56] IB/hfi1: Correct issues with sc5 computation Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 19/56] IB/hfi1: Fix deadlock with txreq allocation slow path Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 20/56] apparmor: fix ref count leak when profile sha1 hash is read Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 21/56] regulator: qcom_smd: Remove list_voltage callback for rpm_smps_ldo_ops_fixed Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 22/56] random: strengthen input validation for RNDADDTOENTCNT Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 23/56] x86/mm/pat: Add support of non-default PAT MSR setting Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 24/56] x86/mm/pat: Add pat_disable() interface Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 25/56] x86/mm/pat: Replace cpu_has_pat with boot_cpu_has() Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 26/56] x86/mtrr: Fix Xorg crashes in Qemu sessions Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 27/56] x86/mtrr: Fix PAT init handling when MTRR is disabled Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 28/56] x86/xen, pat: Remove PAT table init code from Xen Greg Kroah-Hartman
2016-08-14 20:37 ` Greg Kroah-Hartman [this message]
2016-08-14 20:37 ` [PATCH 4.6 30/56] x86/mm/pat: Fix BUG_ON() in mmap_mem() on QEMU/i386 Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 31/56] udf: Prevent stack overflow on corrupted filesystem mount Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 32/56] powerpc/eeh: Fix invalid cached PE primary bus Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 33/56] powerpc/bpf/jit: Disable classic BPF JIT on ppc64le Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 34/56] mm: memcontrol: fix swap counter leak on swapout from offline cgroup Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 35/56] mm: memcontrol: fix memcg id ref counter on swap charge move Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 36/56] x86/syscalls/64: Add compat_sys_keyctl for 32-bit userspace Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 37/56] block: fix use-after-free in seq file Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 38/56] sysv, ipc: fix security-layer leaking Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 39/56] radix-tree: account nodes to memcg only if explicitly requested Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 40/56] x86/microcode: Fix suspend to RAM with builtin microcode Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 41/56] x86/power/64: Fix hibernation return address corruption Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 42/56] fuse: fsync() did not return IO errors Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 43/56] fuse: fuse_flush must check mapping->flags for errors Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 44/56] fuse: fix wrong assignment of ->flags in fuse_send_init() Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 45/56] Revert "mm, mempool: only set __GFP_NOMEMALLOC if there are free elements" Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 46/56] fs/dcache.c: avoid soft-lockup in dput() Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 47/56] Revert "cpufreq: pcc-cpufreq: update default value of cpuinfo_transition_latency" Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 48/56] crypto: gcm - Filter out async ghash if necessary Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 49/56] crypto: scatterwalk - Fix test in scatterwalk_done Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 50/56] serial: mvebu-uart: free the IRQ in ->shutdown() Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 51/56] ext4: check for extents that wrap around Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 52/56] ext4: fix deadlock during page writeback Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 53/56] ext4: dont call ext4_should_journal_data() on the journal inode Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 54/56] ext4: validate s_reserved_gdt_blocks on mount Greg Kroah-Hartman
2016-08-14 20:37 ` [PATCH 4.6 55/56] ext4: short-cut orphan cleanup on error Greg Kroah-Hartman
2016-08-14 20:38 ` [PATCH 4.6 56/56] ext4: fix reference counting bug on block allocation error Greg Kroah-Hartman
2016-08-15 13:07 ` [PATCH 4.6 00/56] 4.6.7-stable review Guenter Roeck
2016-08-16 4:02 ` Shuah Khan
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