Commit Graph

7 Commits

Author SHA1 Message Date
H. Peter Anvin 5400743db5 x86, mtrr: make mtrr_aps_delayed_init static bool
mtr_aps_delayed_init was declared u32 and made global, but it only
ever takes boolean values and is only ever used in
arch/x86/kernel/cpu/mtrr/main.c.  Declare it "static bool" and remove
external references.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
2009-08-21 17:00:02 -07:00
Suresh Siddha d0af9eed5a x86, pat/mtrr: Rendezvous all the cpus for MTRR/PAT init
SDM Vol 3a section titled "MTRR considerations in MP systems" specifies
the need for synchronizing the logical cpu's while initializing/updating
MTRR.

Currently Linux kernel does the synchronization of all cpu's only when
a single MTRR register is programmed/updated. During an AP online
(during boot/cpu-online/resume)  where we initialize all the MTRR/PAT registers,
we don't follow this synchronization algorithm.

This can lead to scenarios where during a dynamic cpu online, that logical cpu
is initializing MTRR/PAT with cache disabled (cr0.cd=1) etc while other logical
HT sibling continue to run (also with cache disabled because of cr0.cd=1
on its sibling).

Starting from Westmere, VMX transitions with cr0.cd=1 don't work properly
(because of some VMX performance optimizations) and the above scenario
(with one logical cpu doing VMX activity and another logical cpu coming online)
can result in system crash.

Fix the MTRR initialization by doing rendezvous of all the cpus. During
boot and resume, we delay the MTRR/PAT init for APs till all the
logical cpu's come online and the rendezvous process at the end of AP's bringup,
will initialize the MTRR/PAT for all AP's.

For dynamic single cpu online, we synchronize all the logical cpus and
do the MTRR/PAT init on the AP that is coming online.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-08-21 16:25:55 -07:00
Jaswinder Singh Rajput d122072cc0 headers_check fix: x86, mtrr.h
fix the following 'make headers_check' warning:

  usr/include/asm/mtrr.h:61: found __[us]{8,16,32,64} type without #include <linux/types.h>

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
2009-01-31 00:17:39 +05:30
Kyle McMartin 79f3b3cb7a x86, mtrr: fix types used in userspace exported header
Commit 932d27a791 exported some mtrr
structures without using the exportable __uX types, causing userspace
build failures.

Signed-off-by: Kyle McMartin <kyle@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-08 16:13:59 +01:00
Sheng Yang 932d27a791 x86: Export some definition of MTRR
For KVM can reuse the type define, and need them to support shadow MTRR.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:51:44 +02:00
H. Peter Anvin 1965aae3c9 x86: Fix ASM_X86__ header guards
Change header guards named "ASM_X86__*" to "_ASM_X86_*" since:

a. the double underscore is ugly and pointless.
b. no leading underscore violates namespace constraints.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-22 22:55:23 -07:00
Al Viro bb8985586b x86, um: ... and asm-x86 move
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-22 22:55:20 -07:00