linux.git/arch/i386/kernel/cpu, branch v2.6.22

MTRR: Fix race causing set_mtrr to go into infinite loop

2007-07-06T17:23:43+00:00

Processors synchronization in set_mtrr requires the .gate field to be set
after .count field is properly initialized.  Without an explicit barrier,
the compiler was reordering those memory stores.  That was sometimes
causing a processor (in ipi_handler) to see the .gate change and decrement
.count before the latter is set by set_mtrr() (which then hangs in a
infinite loop with irqs disabled).

Signed-off-by: Loic Prylli 
Cc: Andi Kleen 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Revert perfctr reservation to 2.6.21 state

2007-07-04T01:11:35+00:00

With this change it works again when the nmi watchdog is disabled.

Signed-off-by: Andi Kleen 
Cc: Björn Steinbrink 
Cc: Stephane Eranian 
Cc: Andrew Morton 
Signed-off-by: Linus Torvalds

i386: mtrr crash fix

2007-07-01T19:29:44+00:00

Commit 3ebad5905609476a4ff1151a66b21d9794009961 ("[PATCH] x86: Save and
restore the fixed-range MTRRs of the BSP when suspending") added mtrr
operations without verifying that the CPU has MTRRs.  Crashes transmeta
CPUs.

Cc: "H. Peter Anvin" 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

i386: remove bogus mtrr range check

2007-07-01T17:56:11+00:00

Commit 9215da33209b861b01c51382254b178a3fe92a30 "fixed" the MTRR range
check to not allow any MTRR's under the 1MB mark (since that's where the
fixed MTRR's are active).

However, that was totally bogus, since it's normal (and almost required)
to have a large variable MTRR that starts at 0, and covers some large
percentage of the whole RAM, and then using the fixed MTRR's to override
that large MTRR to handle the special ISA hole in the 640k-1M region.

The old check was bogus too (checking that no variable MTRR is used that
is entirely under the 1MB range), but at least it wasn't actively
detrimental, because no sane situation would ever trigger such MTRR
usage in the first place.

That said, the whole notion of not allowing variable MTRR's in the low
1MB is just stupid, so rather than revert the commit, this just removes
the whole sad and unnecessary check entirely.

Cc: Jan Beulich 
Cc: Andi Kleen 
Cc: Andrew Morton 
Tested-by: Luca Palermo 
Signed-off-by: Linus Torvalds

mtrr/cyrix: fix sections

2007-06-28T18:34:53+00:00

main.c::mtrr_add() or mtrr_del() [exported]
calls main.c::mtrr_add_page() or mtrr_del_page() or mtrr_restore() [resume]
calls main.c::set_mtrr()
calls main.c::ipi_handler()
calls main.c::mtrr_if->set_all() == which can be cyrix_set_all

WARNING: arch/i386/kernel/built-in.o(.text+0x8657): Section mismatch: reference to .init.data: (between 'cyrix_set_all' and 'centaur_get_free_region')
WARNING: arch/i386/kernel/built-in.o(.text+0x866b): Section mismatch: reference to .init.data: (between 'cyrix_set_all' and 'centaur_get_free_region')
WARNING: arch/i386/kernel/built-in.o(.text+0x867e): Section mismatch: reference to .init.data: (between 'cyrix_set_all' and 'centaur_get_free_region')
WARNING: arch/i386/kernel/built-in.o(.text+0x8684): Section mismatch: reference to .init.data: (between 'cyrix_set_all' and 'centaur_get_free_region')
WARNING: arch/i386/kernel/built-in.o(.text+0x868a): Section mismatch: reference to .init.data: (between 'cyrix_set_all' and 'centaur_get_free_region')

Signed-off-by: Randy Dunlap 
Cc: Andi Kleen 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

x86_64: fix link warning between for .text and .init.text

2007-06-20T21:27:26+00:00

WARNING: arch/x86_64/kernel/built-in.o(.text+0xace9): Section mismatch: reference to .init.text: (between 'get_mtrr_state' and 'mtrr_wrmsr')
WARNING: arch/x86_64/kernel/built-in.o(.text+0xad09): Section mismatch: reference to .init.text: (between 'get_mtrr_state' and 'mtrr_wrmsr')
WARNING: arch/x86_64/kernel/built-in.o(.text+0xad38): Section mismatch: reference to .init.text: (between 'get_mtrr_state' and 'mtrr_wrmsr')
WARNING: drivers/built-in.o(.text+0x3a680): Section mismatch: reference to .init.text:acpi_map_pxm_to_node (between 'acpi_get_node' and 'acpi_lock_ac_dir')

AK: also marked mtrr_bp_init __init to avoid some more warnings

Signed-off-by: Yinghai Lu 
Signed-off-by: Andi Kleen 
Acked-by: Jan Beulich 
Signed-off-by: Linus Torvalds

perfctr-watchdog: fix interchanged parameters to release_{evntsel,perfctr}_nmi

2007-06-16T20:16:15+00:00

Fix oops triggered during: echo 0 > /proc/sys/kernel/nmi_watchdog

The culprit seems to be 09198e68501a7e34737cd9264d266f42429abcdc:
[PATCH] i386: Clean up NMI watchdog code

In two places, the parameters to release_{evntsel,perfctr}_nmi
got interchanged during the cleanup.

Fix interchanged parameters to release_{evntsel,perfctr}_nmi.

Signed-off-by: Björn Steinbrink 
Cc: Stephane Eranian 
Cc: Andi Kleen 
Cc: Michal Piotrowski 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

i386: use the right wrapper to disable the NMI watchdog

2007-06-16T20:16:15+00:00

When disabled through /proc/sys/kernel/nmi_watchdog, the NMI watchdog uses the
stop() method directly, which does not decrement the activity counter, leading
to a BUG().  Use the wrapper function instead to fix that.

Signed-off-by: Björn Steinbrink 
Cc: Andi Kleen 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

i386: fix NMI watchdog not reserving its MSRs

2007-06-16T20:16:15+00:00

At system boot time, the NMI watchdog no longer reserved its MSRs, allowing
other subsystems to mess with them.  Fix that.

Signed-off-by: Björn Steinbrink 
Cc: Andi Kleen 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mtrr atomicity fix

2007-06-04T20:25:09+00:00

Rafael gets this on an SMP box with kernel preemption enabled, during
hibernation and restore (100% of the time):

Enabling non-boot CPUs ...
BUG: using smp_processor_id() in preemptible [00000001] code: bash/4514
caller is mtrr_save_state+0x9/0x40

Cc: "Rafael J. Wysocki" 
Cc: Andi Kleen 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds