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path: root/arch/arm/kernel/unwind.c
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2011-12-15ARM: unwinder: fix bisection to find origin in .idx sectionUwe Kleine-König
The bisection implemented in unwind_find_origin() stopped to early. If there is only a single entry left to check the original code just took the end point as origin which might be wrong. This was introduced in commit de66a979012d ("ARM: 7187/1: fix unwinding for XIP kernels"). Reported-and-tested-by: Nick Bowler <nbowler@elliptictech.com> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-06ARM: 7187/1: fix unwinding for XIP kernelsUwe Kleine-König
The linker places the unwind tables in readonly sections. So when using an XIP kernel these are located in ROM and cannot be modified. For that reason the current approach to convert the relative offsets in the unwind index to absolute addresses early in the boot process doesn't work with XIP. The offsets in the unwind index section are signed 31 bit numbers and the structs are sorted by this offset. So it first has offsets between 0x40000000 and 0x7fffffff (i.e. the negative offsets) and then offsets between 0x00000000 and 0x3fffffff. When seperating these two blocks the numbers are sorted even when interpreting the offsets as unsigned longs. So determine the first non-negative entry once and track that using the new origin pointer. The actual bisection can then use a plain unsigned long comparison. The only thing that makes the new bisection more complicated is that the offsets are relative to their position in the index section, so the key to search needs to be adapted accordingly in each step. Moreover several consts are added to catch future writes and rename the member "addr" of struct unwind_idx to "addr_offset" to better match the new semantic. (This has the additional benefit of breaking eventual users at compile time to make them aware of the change.) In my tests the new algorithm was a tad faster than the original and has the additional upside of not needing the initial conversion and so saves some boot time and it's possible to unwind even earlier. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-10-31arm: convert core files from module.h to export.hPaul Gortmaker
Many of the core ARM kernel files are not modules, but just including module.h for exporting symbols. Now these files can use the lighter footprint export.h for this role. There are probably lots more, but ARM files of mach-* and plat-* don't get coverage via a simple yesconfig build. They will have to be cleaned up and tested via using their respective configs. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2010-11-07ARM: 6468/1: backtrace: fix calculation of thread stack baseWill Deacon
When unwinding stack frames we must take care not to unwind areas of memory that lie outside of the known extent of the stack. This patch fixes an incorrect calculation of the stack base where THREAD_SIZE is added to the stack pointer after it has already been aligned to this value. Since the ALIGN macro performs this addition internally, we end up overshooting the base by 8k. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-09-02ARM: 6341/1: unwind - optimise linked-list searches for modulesPhil Carmody
With several sections per module, and dozens of modules, the searches down the linked list of sections would dominate the lookup time, dwarfing any savings from the binary search within the section. A simple move-to-front optimisation exploits the commonality of the code paths taken, and in simple real-world tests reduces the number of steps in the search to barely more than 1. Signed-off-by: Phil Carmody <ext-phil.2.carmody@nokia.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-05-24ARM: 6140/1: silence a bogus sparse warning in unwind.cAlexander Shishkin
The check for compiler which is supposed to miscompile unwind tables clearly has nothing to do with sparse (which does not define necessary macros anyway), so simply silence it. Signed-off-by: Alexander Shishkin <virtuoso@slind.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-03-07ARM: 5977/1: arm: Enable backtrace printing on oops when PC is corruptedLaurent Pinchart
If PC points outside kernel text, start printing the backtrace at LR instead. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-11-02ARM: 5776/1: Check compiler version and EABI support when adding ARM unwind ↵Claudio Scordino
support. ARM unwind is known to compile only with EABI and not-buggy compilers. The problem is not the unwinding information but the -fno-frame-pointer option added as a result of !CONFIG_FRAME_POINTER. Now we check the compiler and raise a #warning in case of wrong compiler. Signed-off-by: Claudio Scordino <claudio@evidence.eu.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-07-24Thumb-2: Implementation of the unified start-up and exceptions codeCatalin Marinas
This patch implements the ARM/Thumb-2 unified kernel start-up and exception handling code. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2009-06-19[ARM] 5558/1: Add extra checks to ARM unwinder to avoid tracing corrupt stacksCatalin Marinas
There are situations where the unwinder goes beyond stack boundaries and unwinds random data. This patch moves the stack boundaries check after the unwind_exec_insn() call and adds an extra check for possible infinite loops (like "mov pc, lr" with pc == lr). The patch also fixes a bug in the unwind instructions interpreter. The 0xb0 instruction can only set PC to LR if this wasn't already set by a previous instruction (this is used on exceptions taken while in kernel mode where svc_entry is annotated with ".save {r0 - pc}"). Tested-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-19[ARM] 5383/2: unwind: Add core support for ARM stack unwindingCatalin Marinas
This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>