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2008-01-26ARM kprobes: special hook for the kprobes breakpoint handlerNicolas Pitre
The kprobes code is already able to cope with reentrant probes, so its handler must be called outside of the region protected by undef_lock. If ever this lock is released when handlers are called then this commit could be reverted. Signed-off-by: Nicolas Pitre <nico@marvell.com>
2008-01-26ARM kprobes: prevent some functions involved with kprobes from being probedNicolas Pitre
Signed-off-by: Nicolas Pitre <nico@marvell.com>
2007-11-26[ARM] 4659/1: remove possibilities for spurious false negative with ↵Nicolas Pitre
__kuser_cmpxchg The ARM __kuser_cmpxchg routine is meant to implement an atomic cmpxchg in user space. It however can produce spurious false negative if a processor exception occurs in the middle of the operation. Normally this is not a problem since cmpxchg is typically called in a loop until it succeeds to implement an atomic increment for example. Some use cases which don't involve a loop require that the operation be 100% reliable though. This patch changes the implementation so to reattempt the operation after an exception has occurred in the critical section rather than abort it. Here's a simple program to test the fix (don't use CONFIG_NO_HZ in your kernel as this depends on a sufficiently high interrupt rate): #include <stdio.h> typedef int (__kernel_cmpxchg_t)(int oldval, int newval, int *ptr); #define __kernel_cmpxchg (*(__kernel_cmpxchg_t *)0xffff0fc0) int main() { int i, x = 0; for (i = 0; i < 100000000; i++) { int v = x; if (__kernel_cmpxchg(v, v+1, &x)) printf("failed at %d: %d vs %d\n", i, v, x); } printf("done with %d vs %d\n", i, x); return 0; } Signed-off-by: Nicolas Pitre <nico@marvell.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-11-26[ARM] 4661/1: fix do_undefinstr wrt the enabling of IRQsNicolas Pitre
The lock is acquired with spin_lock_irqsave() and released in the not-found case with spin_unlock_irqrestore(). Signed-off-by: Nicolas Pitre <nico@marvell.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-10-19Use helpers to obtain task pid in printks (arch code)Alexey Dobriyan
One of the easiest things to isolate is the pid printed in kernel log. There was a patch, that made this for arch-independent code, this one makes so for arch/xxx files. It took some time to cross-compile it, but hopefully these are all the printks in arch code. Signed-off-by: Alexey Dobriyan <adobriyan@openvz.org> Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-26[ARM] Remove CONFIG_IGNORE_FIQRussell King
IGNORE_FIQ does not appear in the Kconfig files, so can be removed. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-07-17Report that kernel is tainted if there was an OOPSPavel Emelianov
If the kernel OOPSed or BUGed then it probably should be considered as tainted. Thus, all subsequent OOPSes and SysRq dumps will report the tainted kernel. This saves a lot of time explaining oddities in the calltraces. Signed-off-by: Pavel Emelianov <xemul@openvz.org> Acked-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> [ Added parisc patch from Matthew Wilson -Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-05[ARM] always allow dump_stack() to produce a backtraceRussell King
Don't make this dependent on CONFIG_DEBUG_KERNEL - if we hit a WARN_ON we need the stack trace to work out how we got to that point. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-06-17[ARM] Add support for pause_on_oops and display preempt/smp optionsRussell King
Add calls to oops_enter() and oops_exit() to __die(), so that things like lockdep know when an oops occurs. Add suffixes to the oops report to indicate whether the running kernel has been built with preempt or smp support. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-05-08move die notifier handling to common codeChristoph Hellwig
This patch moves the die notifier handling to common code. Previous various architectures had exactly the same code for it. Note that the new code is compiled unconditionally, this should be understood as an appel to the other architecture maintainer to implement support for it aswell (aka sprinkling a notify_die or two in the proper place) arm had a notifiy_die that did something totally different, I renamed it to arm_notify_die as part of the patch and made it static to the file it's declared and used at. avr32 used to pass slightly less information through this interface and I brought it into line with the other architectures. [akpm@linux-foundation.org: build fix] [akpm@linux-foundation.org: fix vmalloc_sync_all bustage] [bryan.wu@analog.com: fix vmalloc_sync_all in nommu] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: <linux-arch@vger.kernel.org> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Bryan Wu <bryan.wu@analog.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-03[ARM] 4356/1: arm: fix handling of svc mode undefined instructionsDan Williams
Now that do_undefinstr handles kernel and user mode undefined instruction exceptions it must not assume that interrupts are enabled at entry. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-04-21[ARM] Remove needless linux/ptrace.h includesRussell King
Lots of places in arch/arm were needlessly including linux/ptrace.h, resumably because we used to pass a struct pt_regs to interrupt handlers. Now that we don't, all these ptrace.h includes are redundant. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-04-21[ARM] Add ability to dump exception stacks to kernel backtracesRussell King
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-02-14[ARM] 4183/1: do_undefinstr: read svc undefined instructions with svc privilegesDan Williams
do_undefinstr currently does not expect undefined instructions in kernel code, since it always uses get_user() to read the instruction. Dereference the 'pc' pointer directly in the SVC case. Per Nicolas Pitre's note, kernel code is never in thumb mode. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-02-06[ARM] Move processor_modes[] to .../process.cRussell King
bad_mode() currently prints the mode which caused the exception, and then causes an oops dump to be printed which again displays this information (since the CPSR in the struct pt_regs is correct.) This leads to processor_modes[] being shared between traps.c and process.c with a local declaration of it. We can clean this up by moving processor_modes[] to process.c and removing the duplication, resulting in processor_modes[] becoming static. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-01-06[ARM] 4070/1: arch/arm/kernel: fix warnings from missing includesBen Dooks
Include <asm/io.h> to fix the warning: arch/arm/kernel/traps.c:647:6: warning: symbol '__readwrite_bug' was not declared. Should it be static? Include <linux/mc146818rtc.h> to fix the warning: arch/arm/kernel/time.c:42:1: warning: symbol 'rtc_lock' was not declared. Should it be static? Signed-off-by: Ben Dooks <ben-linux@fluff.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-12-07[ARM] 3983/2: remove unused argument to __bug()Nicolas Pitre
It appears that include/asm-arm/bug.h requires include/linux/stddef.h for the definition of NULL. It seems that stddef.h was always included indirectly in most cases, and that issue was properly fixed a while ago. Then commit 5047f09b56d0bc3c21aec9cb16de60283da645c6 incorrectly reverted change from commit ff10952a547dad934d9ed9afc5cf579ed1ccb53a (bad dwmw2) and the problem recently resurfaced. Because the third argument to __bug() is never used anyway, RMK suggested getting rid of it entirely instead of readding #include <linux/stddef.h> which this patch does. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-09-20[ARM] 3759/2: Remove uses of %?Daniel Jacobowitz
Patch from Daniel Jacobowitz The ARM kernel has several uses of asm("foo%?"). %? is a GCC internal modifier used to output conditional execution predicates. However, no version of GCC supports conditionalizing asm statements. GCC 4.2 will correctly expand %? to the empty string in user asms. Earlier versions may reuse the condition from the previous instruction. In 'if (foo) asm ("bar%?");' this is somewhat likely to be right... but not reliable. So, the only safe thing to do is to remove the uses of %?. I believe the tlbflush.h occurances were supposed to be removed before, based on the comment about %? not working at the top of that file. Old versions of GCC could omit branches around user asms if the asm didn't mark the condition codes as clobbered. This problem hasn't been seen on any recent (3.x or 4.x) GCC, but it could theoretically happen. So, where %? was removed a cc clobber was added. Signed-off-by: Daniel Jacobowitz <dan@codesourcery.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-08-14[PATCH] Change panic_on_oops message to "Fatal exception"Horms
Previously the message was "Fatal exception: panic_on_oops", as introduced in a recent patch whith removed a somewhat dangerous call to ssleep() in the panic_on_oops path. However, Paul Mackerras suggested that this was somewhat confusing, leadind people to believe that it was panic_on_oops that was the root cause of the fatal exception. On his suggestion, this patch changes the message to simply "Fatal exception". A suitable oops message should already have been displayed. Signed-off-by: Simon Horman <horms@verge.net.au> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-31[PATCH] panic_on_oops: remove ssleep()Horms
This patch is part of an effort to unify the panic_on_oops behaviour across all architectures that implement it. It was pointed out to me by Andi Kleen that if an oops has occured in interrupt context, then calling sleep() in the oops path will only cause a panic, and that it would be really better for it not to be in the path at all. This patch removes the ssleep() call and reworks the console message accordinly. I have a slght concern that the resulting console message is too long, feedback welcome. For powerpc it also unifies the 32bit and 64bit behaviour. Fror x86_64, this patch only updates the console message, as ssleep() is already not present. Signed-off-by: Horms <horms@verge.net.au> Acked-by: Paul Mackerras <paulus@samba.org> Cc: Russell King <rmk@arm.linux.org.uk> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Andi Kleen <ak@muc.de> Cc: Chris Zankel <chris@zankel.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-30Remove obsolete #include <linux/config.h>Jörn Engel
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-03-28Merge nommu treeRussell King
2006-03-27[ARM] nommu: fixups for the exception vectorsHyok S. Choi
The high page vector (0xFFFF0000) does not supported in nommu mode. This patch allows the vectors to be 0x00000000 or the begining of DRAM in nommu mode. Signed-off-by: Hyok S. Choi <hyok.choi@samsung.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-03-25[ARM] 3030/2: fix permission check in the obscur cmpxchg syscallNicolas Pitre
Patch from Nicolas Pitre Quoting RMK: |pte_write() just says that the page _may_ be writable. It doesn't say |that the MMU is programmed to allow writes. If pte_dirty() doesn't |return true, that means that the page is _not_ writable from userspace. |If you write to it from kernel mode (without using put_user) you'll |bypass the MMU read-only protection and may end up writing to a page |owned by two separate processes. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-02-22[ARM] Add panic-on-oops supportRussell King
Although you could ask the kernel for panic-on-oops, it remained non-functional because the architecture specific code fragment had not been implemented. Add it, so it works as advertised. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-01-14[ARM] 3105/4: ARM EABI: new syscall entry conventionNicolas Pitre
Patch from Nicolas Pitre For a while we wanted to change the way syscalls were called on ARM. Instead of encoding the syscall number in the swi instruction which requires reading back the instruction from memory to extract that number and polluting the data cache, it was decided that simply storing the syscall number into r7 would be more efficient. Since this represents an ABI change then making that change at the same time as EABI support is the right thing to do. It is now expected that EABI user space binaries put the syscall number into r7 and use "swi 0" to call the kernel. Syscall register argument are also expected to have "EABI arrangement" i.e. 64-bit arguments should be put in a pair of registers from an even register number. Example with long ftruncate64(unsigned int fd, loff_t length): legacy ABI: - put fd into r0 - put length into r1-r2 - use "swi #(0x900000 + 194)" to call the kernel new ARM EABI: - put fd into r0 - put length into r2-r3 (skipping over r1) - put 194 into r7 - use "swi 0" to call the kernel Note that it is important to use 0 for the swi argument as backward compatibility with legacy ABI user space relies on this. The syscall macros in asm-arm/unistd.h were also updated to support both ABIs and implement the right call method automatically. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-01-12[PATCH] arm: task_stack_page()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-12[PATCH] arm: end_of_stack()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-03[ARM] Cleanup ARM includesRussell King
arch/arm/kernel/entry-armv.S has contained a comment suggesting that asm/hardware.h and asm/arch/irqs.h should be moved into the asm/arch/entry-macro.S include. So move the includes to these two files as required. Add missing includes (asm/hardware.h, asm/io.h) to asm/arch/system.h includes which use those facilities, and remove asm/io.h from kernel/process.c. Remove other unnecessary includes from arch/arm/kernel, arch/arm/mm and arch/arm/mach-footbridge. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-10-30[ARM] Re-organise die()Russell King
Provide __die() which can be called from various contexts to provide an oops report. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-10-29[PATCH] mm: arm ready for split ptlockHugh Dickins
Prepare arm for the split page_table_lock: three issues. Signal handling's preserve and restore of iwmmxt context currently involves reading and writing that context to and from user space, while holding page_table_lock to secure the user page(s) against kswapd. If we split the lock, then the structure might span two pages, secured by to read into and write from a kernel stack buffer, copying that out and in without locking (the structure is 160 bytes in size, and here we're near the top of the kernel stack). Or would the overhead be noticeable? arm_syscall's cmpxchg emulation use pte_offset_map_lock, instead of pte_offset_map and mm-wide page_table_lock; and strictly, it should now also take mmap_sem before descending to pmd, to guard against another thread munmapping, and the page table pulled out beneath this thread. Updated two comments in fault-armv.c. adjust_pte is interesting, since its modification of a pte in one part of the mm depends on the lock held when calling update_mmu_cache for a pte in some other part of that mm. This can't be done with a split page_table_lock (and we've already taken the lowest lock in the hierarchy here): so we'll have to disable split on arm, unless CONFIG_CPU_CACHE_VIPT to ensures adjust_pte never used. Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-28[ARM] 3035/1: RISCOS compat code fixNicolas Pitre
Patch from Nicolas Pitre From: Daniel Jacobowitz <dan@debian.org> > I also fixed a bug that confused me greatly while trying to debug: one > SIGILL has long been a SIGSEGV because of some broken RISCOS > compatibility code. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-10-04[ARM] 2951/1: fix wrong commentNicolas Pitre
Patch from Nicolas Pitre The cmpxchg emulation syscall needs write access. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-09-21[ARM] 2932/1: Avoid the "noreturn" warning in arch/arm/kernel/traps.cCatalin Marinas
Patch from Catalin Marinas This patch prevents the "noreturn function does return" warning in the __bug() function in arch/arm/kernel/traps.c Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-08-23[PATCH] qualifiers in return types - easy casesAl Viro
a bunch of functions switched from volatile to __attribute__((noreturn)) and from const to __attribute_pure__ Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-16[PATCH] ARM: Allow register_undef_hook to be called with IRQs offRussell King
Preserve the interrupt status across a call to register_undef_hook. This allows it to be called while interrupts are disabled. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-06-30[PATCH] ARM: Don't try to send a signal to pid0Russell King
If we receive an unrecognised abort during boot, don't try to send a signal to pid0, but instead report the current state. This leads to less confusing debug reports. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-06-22[PATCH] ARM: Move signal return code into vector pageRussell King
Move the signal return code into the vector page instead of placing it on the user mode stack, which will allow us to avoid flushing the instruction cache on signals, as well as eventually allowing non-exec stack. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-06-08[PATCH] ARM: 2664/2: add support for atomic ops on pre-ARMv6 SMP systemsNicolas Pitre
Patch from Nicolas Pitre Not that there might be many of them on the planet, but at least RMK apparently has one. Signed-off-by: Nicolas Pitre Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-05-05[PATCH] ARM: 2663/1: straightify TLS register emulation a bit moreNicolas Pitre
Patch from Nicolas Pitre This better express things, and should cover RMK's weird SMP toys. Signed-off-by: Nicolas Pitre Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-05-05[PATCH] ARM: Fix kernel stack offset calculationsRussell King
Various places in the ARM kernel implicitly assumed that kernel stacks are always 8K due to hard coded constants. Replace these constants with definitions. Correct the allowable range of kernel stack pointer values within the allocation. Arrange for the entire kernel stack to be zeroed, not just the upper 4K if CONFIG_DEBUG_STACK_USAGE is set. Signed-off-by: Russell King <rmk@arm.linux.org.uk>
2005-04-29[PATCH] ARM: 2651/3: kernel helpers for NPTL supportNicolas Pitre
Patch from Nicolas Pitre This patch entirely reworks the kernel assistance for NPTL on ARM. In particular this provides an efficient way to retrieve the TLS value and perform atomic operations without any instruction emulation nor special system call. This even allows for pre ARMv6 binaries to be forward compatible with SMP systems without any penalty. The problematic and performance critical operations are performed through segment of kernel provided user code reachable from user space at a fixed address in kernel memory. Those fixed entry points are within the vector page so we basically get it for free as no extra memory page is required and nothing else may be mapped at that location anyway. This is different from (but doesn't preclude) a full blown VDSO implementation, however a VDSO would prevent some assembly tricks with constants that allows for efficient branching to those code segments. And since those code segments only use a few cycles before returning to user code, the overhead of a VDSO far call would add a significant overhead to such minimalistic operations. The ARM_NR_set_tls syscall also changed number. This is done for two reasons: 1) this patch changes the way the TLS value was previously meant to be retrieved, therefore we ensure whatever library using the old way gets fixed (they only exist in private tree at the moment since the NPTL work is still progressing). 2) the previous number was allocated in a range causing an undefined instruction trap on kernels not supporting that syscall and it was determined that allocating it in a range returning -ENOSYS would be much nicer for libraries trying to determine if the feature is present or not. Signed-off-by: Nicolas Pitre Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-04-26[PATCH] ARM: remove some entry initialisation asm codeRussell King
Convert the trivial vector entry initialisation code to C code. Signed-off-by: Russell King <rmk@arm.linux.org.uk>
2005-04-17[PATCH] ARM: showregsRussell King
Fix show_regs() to provide a backtrace. Provide a new __show_regs() function which implements the common subset of show_regs() and die(). Add prototypes to asm-arm/system.h Signed-off-by: Russell King <rmk@arm.linux.org.uk>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!