Fix this sparse warning:
arch/x86/mm/numa_32.c:197:24: warning: Using plain integer as NULL pointer
Signed-off-by: Hannes Eder <hannes@hanneseder.net>
Cc: trivial@kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Fix these sparse warnings:
arch/x86/kernel/machine_kexec_32.c:124:22: warning: Using plain integer as NULL pointer
arch/x86/kernel/traps.c:950:24: warning: Using plain integer as NULL pointer
Signed-off-by: Hannes Eder <hannes@hanneseder.net>
Cc: trivial@kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
As acpi_enter_sleep_state can fail, take this into account in
do_suspend_lowlevel and don't return to the do_suspend_lowlevel's
caller. This would break (currently) fpu status and preempt count.
Technically, this means use `call' instead of `jmp' and `jmp' to
the `resume_point' after the `call' (i.e. if
acpi_enter_sleep_state returns=fails). `resume_point' will handle
the restore of fpu and preempt count gracefully.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
- remove %ds re-set, it's already set in wakeup_long64
- remove double labels and alignment (ENTRY already adds both)
- use meaningful resume point labelname
- skip alignment while jumping from wakeup_long64 to the resume point
- remove .size, .type and unused labels
[v2]
- added ENDPROCs
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
Impact: Bug fix on UP
Checkin 6ec68bff3c81e776a455f6aca95c8c5f1d630198:
x86, mce: reinitialize per cpu features on resume
introduced a call to mce_cpu_features() in the resume path, in order
for the MCE machinery to get properly reinitialized after a resume.
However, this function (and its successors) was flagged __cpuinit,
which becomes __init on UP configurations (on SMP suspend/resume
requires CPU hotplug and so this would not be seen.)
Remove the offending __cpuinit annotations for mce_cpu_features() and
its successor functions.
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: use the right protections for split-up pagetables
x86, vmi: TSC going backwards check in vmi clocksource
oprofile for MN10300 seems to have been broken by the advent of the new
tracing framework.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Impact: extend prefetch handling on 64-bit
Currently there's an extra is_prefetch() check done in do_sigbus(),
which we only do on 32 bits.
This is a last-ditch check before we terminate a task, so it's worth
giving prefetch instructions another chance - should none of our
existing quirks have caught a prefetch instruction related spurious
fault.
The only risk is if a prefetch causes a real sigbus, in that case
we'll not OOM but try another fault. But this code has been on
32-bit for a long time, so it should be fine in practice.
So do this on 64-bit too - and thus remove one more #ifdef.
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
Removal of an #ifdef in fault_in_kernel_space(), by making
use of the new TASK_SIZE_MAX symbol which is now available
on 32-bit too.
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
Rename TASK_SIZE64 to TASK_SIZE_MAX, and provide the
define on 32-bit too. (mapped to TASK_SIZE)
This allows 32-bit code to make use of the (former-) TASK_SIZE64
symbol as well, in a clean way.
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
do_page_fault() has this ugly #ifdef in its prototype:
#ifdef CONFIG_X86_64
asmlinkage
#endif
void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code)
Replace it with 'dotraplinkage' which maps to exactly the above
construct: nothing on 32-bit and asmlinkage on 64-bit.
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: add oops-recursion check to 32-bit
Unify the oops state-machine, to the 64-bit version. It is
slightly more careful in that it does a recursion check
in oops_begin(), and is thus more likely to show the relevant
oops.
It also means that 32-bit will print one more line at the
end of pagefault triggered oopses:
printk(KERN_EMERG "CR2: %016lx\n", address);
Which is generally good information to be seen in partial-dump
digital-camera jpegs ;-)
The downside is the somewhat more complex critical path. Both
variants have been tested well meanwhile by kernel developers
crashing their boxes so i dont think this is a practical worry.
This removes 3 ugly #ifdefs from no_context() and makes the
function a lot nicer read.
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: refine/extend page fault related oops printing on 64-bit
- honor the pause_on_oops logic on 64-bit too
- print out NX fault warnings on 64-bit as well
- factor out the NX fault message to make it git-greppable and readable
Note that this means that we do the PF_INSTR check on 32-bit non-PAE
as well where it should not occur ... normally. Cannot hurt.
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
Remove an #ifdef from notify_page_fault(). The function still
compiles to nothing in the !CONFIG_KPROBES case.
Introduce kprobes_built_in() and kprobe_fault_handler() helpers
to allow this - they returns 0 if !CONFIG_KPROBES.
No code changed:
text data bss dec hex filename
4618 32 24 4674 1242 fault.o.before
4618 32 24 4674 1242 fault.o.after
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
Remove an #ifdef from kmmio_fault() - we can do this by
providing default implementations for is_kmmio_active()
and kmmio_handler(). The compiler optimizes it all away
in the !CONFIG_MMIOTRACE case.
Also, while at it, clean up mmiotrace.h a bit:
- standard header guards
- standard vertical spaces for structure definitions
No code changed (both with mmiotrace on and off in the config):
text data bss dec hex filename
2947 12 12 2971 b9b fault.o.before
2947 12 12 2971 b9b fault.o.after
Cc: Pekka Paalanen <pq@iki.fi>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: improve page fault handling robustness
The 'PF_RSVD' flag (bit 3) of the page-fault error_code is a
relatively recent addition to x86 CPUs, so the 32-bit do_fault()
implementation never had it. This flag gets set when the CPU
detects nonzero values in any reserved bits of the page directory
entries.
Extend the existing 64-bit check for PF_RSVD in do_page_fault()
to 32-bit too. If we detect such a fault then we print a more
informative oops and the pagetables.
This unifies the code some more, removes an ugly #ifdef and improves
the 32-bit page fault code robustness a bit. It slightly increases
the 32-bit kernel text size.
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
Instead of an ugly, open-coded, #ifdef-ed vm86 related legacy check
in do_page_fault(), put it into the check_v8086_mode() helper
function and merge it with an existing #ifdef.
Also, simplify the code flow a tiny bit in the helper.
No code changed:
arch/x86/mm/fault.o:
text data bss dec hex filename
2711 12 12 2735 aaf fault.o.before
2711 12 12 2735 aaf fault.o.after
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: no functionality changed
Factor out the opcode checker into a helper inline.
The code got a tiny bit smaller:
text data bss dec hex filename
4632 32 24 4688 1250 fault.o.before
4618 32 24 4674 1242 fault.o.after
And it got cleaner / easier to review as well.
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup, no code changed
Clean up various small details, which can be correctness checked
automatically:
- tidy up the include file section
- eliminate unnecessary includes
- introduce show_signal_msg() to clean up code flow
- standardize the code flow
- standardize comments and other style details
- more cleanups, pointed out by checkpatch
No code changed on either 32-bit nor 64-bit:
arch/x86/mm/fault.o:
text data bss dec hex filename
4632 32 24 4688 1250 fault.o.before
4632 32 24 4688 1250 fault.o.after
the md5 changed due to a change in a single instruction:
2e8a8241e7f0d69706776a5a26c90bc0 fault.o.before.asm
c5c3d36e725586eb74f0e10692f0193e fault.o.after.asm
Because a __LINE__ reference in a WARN_ONCE() has changed.
On 32-bit a few stack offsets changed - no code size difference
nor any functionality difference.
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
clean up vmi_read_cycles to use max()
Reported-b: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Alok N Kataria <akataria@vmware.com>
Cc: Zach Amsden <zach@vmware.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: future-proof the split_large_page() function
Linus noticed that split_large_page() is not safe wrt. the
PAT bit: it is bit 12 on the 1GB and 2MB page table level
(_PAGE_BIT_PAT_LARGE), and it is bit 7 on the 4K page
table level (_PAGE_BIT_PAT).
Currently it is not a problem because we never set
_PAGE_BIT_PAT_LARGE on any of the large-page mappings - but
should this happen in the future the split_large_page() would
silently lift bit 12 into the lowlevel 4K pte and would start
corrupting the physical page frame offset. Not fun.
So add a debug warning, to make sure if something ever sets
the PAT bit then this function gets updated too.
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix to prevent hard lockup on bad PMD permissions
If the PMD does not have the correct permissions for a page access,
but the PTE does, the spurious fault handler will mistake the fault
as a lazy TLB transaction. This will result in an infinite loop of:
fault -> spurious_fault check (pass) -> return to code -> fault
This patch adds a check and a warn on if the PTE passes the permissions
but the PMD does not.
[ Updated: Ingo Molnar suggested using WARN_ONCE with some text ]
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Steven Rostedt found a bug in where in his modified kernel
ftrace was unable to modify the kernel text, due to the PMD
itself having been marked read-only as well in
split_large_page().
The fix, suggested by Linus, is to not try to 'clone' the
reference protection of a huge-page, but to use the standard
(and permissive) page protection bits of KERNPG_TABLE.
The 'cloning' makes sense for the ptes but it's a confused and
incorrect concept at the page table level - because the
pagetable entry is a set of all ptes and hence cannot
'clone' any single protection attribute - the ptes can be any
mixture of protections.
With the permissive KERNPG_TABLE, even if the pte protections
get changed after this point (due to ftrace doing code-patching
or other similar activities like kprobes), the resulting combined
protections will still be correct and the pte's restrictive
(or permissive) protections will control it.
Also update the comment.
This bug was there for a long time but has not caused visible
problems before as it needs a rather large read-only area to
trigger. Steve possibly hacked his kernel with some really
large arrays or so. Anyway, the bug is definitely worth fixing.
[ Huang Ying also experienced problems in this area when writing
the EFI code, but the real bug in split_large_page() was not
realized back then. ]
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Reported-by: Huang Ying <ying.huang@intel.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix time warps under vmware
Similar to the check for TSC going backwards in the TSC clocksource,
we also need this check for VMI clocksource.
Signed-off-by: Alok N Kataria <akataria@vmware.com>
Cc: Zachary Amsden <zach@vmware.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: stable@kernel.org
arch/ia64/xen/xen_pv_ops.c:156: error: xen_init_ops causes a section type conflict
arch/ia64/xen/xen_pv_ops.c:340: error: xen_iosapic_ops causes a section type conflict
Signed-off-by: Tony Luck <tony.luck@intel.com>
This patch fixes xen related Kconfigs and add default config
file for ia64 xen domU.
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Tony Luck <aegl@agluck-desktop.(none)>
The second call to cpu_clear() is redundant, as we've already removed
the CPU from cpu_online_map before calling migrate_platform_irqs().
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Tony Luck <aegl@agluck-desktop.(none)>
This reverts commit e7b140365b86aaf94374214c6f4e6decbee2eb0a.
Commit e7b14036 removes the targetted disabled CPU from the
cpu_online_map after calls to migrate_platform_irqs and fixup_irqs.
Paul McKenney states that the reasoning behind the patch was to
prevent irq handlers from running on CPUs marked offline because:
RCU happily ignores CPUs that don't have their bits set in
cpu_online_map, so if there are RCU read-side critical sections
in the irq handlers being run, RCU will ignore them. If the
other CPUs were running, they might sequence through the RCU
state machine, which could result in data structures being
yanked out from under those irq handlers, which in turn could
result in oopses or worse.
Unfortunately, both ia64 functions above look at cpu_online_map to find
a new CPU to migrate interrupts onto. This means we can potentially
migrate an interrupt off ourself back to... ourself. Uh oh.
This causes an oops when we finally try to process pending interrupts on
the CPU we want to disable. The oops results from calling __do_IRQ with
a NULL pt_regs:
Unable to handle kernel NULL pointer dereference (address 0000000000000040)
Call Trace:
[<a000000100016930>] show_stack+0x50/0xa0
sp=e0000009c922fa00 bsp=e0000009c92214d0
[<a0000001000171a0>] show_regs+0x820/0x860
sp=e0000009c922fbd0 bsp=e0000009c9221478
[<a00000010003c700>] die+0x1a0/0x2e0
sp=e0000009c922fbd0 bsp=e0000009c9221438
[<a0000001006e92f0>] ia64_do_page_fault+0x950/0xa80
sp=e0000009c922fbd0 bsp=e0000009c92213d8
[<a00000010000c7a0>] ia64_native_leave_kernel+0x0/0x270
sp=e0000009c922fc60 bsp=e0000009c92213d8
[<a0000001000ecdb0>] profile_tick+0xd0/0x1c0
sp=e0000009c922fe30 bsp=e0000009c9221398
[<a00000010003bb90>] timer_interrupt+0x170/0x3e0
sp=e0000009c922fe30 bsp=e0000009c9221330
[<a00000010013a800>] handle_IRQ_event+0x80/0x120
sp=e0000009c922fe30 bsp=e0000009c92212f8
[<a00000010013aa00>] __do_IRQ+0x160/0x4a0
sp=e0000009c922fe30 bsp=e0000009c9221290
[<a000000100012290>] ia64_process_pending_intr+0x2b0/0x360
sp=e0000009c922fe30 bsp=e0000009c9221208
[<a0000001000112d0>] fixup_irqs+0xf0/0x2a0
sp=e0000009c922fe30 bsp=e0000009c92211a8
[<a00000010005bd80>] __cpu_disable+0x140/0x240
sp=e0000009c922fe30 bsp=e0000009c9221168
[<a0000001006c5870>] take_cpu_down+0x50/0xa0
sp=e0000009c922fe30 bsp=e0000009c9221148
[<a000000100122610>] stop_cpu+0xd0/0x200
sp=e0000009c922fe30 bsp=e0000009c92210f0
[<a0000001000e0440>] kthread+0xc0/0x140
sp=e0000009c922fe30 bsp=e0000009c92210c8
[<a000000100014ab0>] kernel_thread_helper+0xd0/0x100
sp=e0000009c922fe30 bsp=e0000009c92210a0
[<a00000010000a4c0>] start_kernel_thread+0x20/0x40
sp=e0000009c922fe30 bsp=e0000009c92210a0
I don't like this revert because it is fragile. ia64 is getting lucky
because we seem to only ever process timer interrupts in this path, but
if we ever race with an IPI here, we definitely use RCU and have the
potential of hitting an oops that Paul describes above.
Patching ia64's timer_interrupt() to check for NULL pt_regs is
insufficient though, as we still hit the above oops.
As a short term solution, I do think that this revert is the right
answer. The revert hold up under repeated testing (24+ hour test runs)
with this setup:
- 8-way rx6600
- randomly toggling CPU online/offline state every 2 seconds
- running CPU exercisers, memory hog, disk exercisers, and
network stressors
- average system load around ~160
In the long term, we really need to figure out why we set pt_regs = NULL
in ia64_process_pending_intr(). If it turns out that it is unnecessary
to do so, then we could safely re-introduce e7b14036 (along with some
other logic to be smarter about migrating interrupts).
One final note: x86 also removes the disabled CPU from cpu_online_map
and then re-enables interrupts for 1ms, presumably to handle any pending
interrupts:
arch/x86/kernel/irq_32.c (and irq_64.c):
cpu_disable_common:
[remove cpu from cpu_online_map]
fixup_irqs():
for_each_irq:
[break CPU affinities]
local_irq_enable();
mdelay(1);
local_irq_disable();
So they are doing implicitly what ia64 is doing explicitly.
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Tony Luck <aegl@agluck-desktop.(none)>
BTE_MAX_XFER is wrong. It is one greater than the number of cache
lines the BTE is actually able to transfer. If you request a transfer
of exactly BTE_MAX_XFER size, you trip a very cryptic BUG_ON() which
should certainly be made more clear.
This patch fixes that constant and also cleans up the BUG_ON()s in
arch/ia64/sn/kernel/bte.c to test one condition per line.
Signed-off-by: Robin Holt <holt@sgi.com>
Signed-off-by: Tony Luck <aegl@agluck-desktop.(none)>
ia64 only defines __early_pfn_to_nid() for SPARSEMEM && NUMA configurations,
so the recent:
commit: f2dbcfa738368c8a40d4a5f0b65dc9879577cb21
mm: clean up for early_pfn_to_nid()
ends up with some link problems for certain configuration files.
Fix arch/ia64/Kconfig to only define HAVE_ARCH_EARLY_PFN_TO_NID in the
cases where we do provide this function.
Signed-off-by: Tony Luck <tony.luck@intel.com>
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, mce: fix ifdef for 64bit thermal apic vector clear on shutdown
x86, mce: use force_sig_info to kill process in machine check
x86, mce: reinitialize per cpu features on resume
x86, rcu: fix strange load average and ksoftirqd behavior
Remove the gesbc9312.h header since it is unused.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Impact: clenaup
Linker script will put startup_32 at predefined
address so using startup_32 will not bloat the
code size.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: clenaup
Linker script will put startup_32 at predefined
address so using ENTRY will not bloat the code
size.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
We are in setup stage so we use GLOBAL
instead of ENTRY and do not increase code
size.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
