linux/arch/arm64/mm
Dave P Martin 9fb7410f95 arm64/BUG: Use BRK instruction for generic BUG traps
Currently, the minimal default BUG() implementation from asm-
generic is used for arm64.

This patch uses the BRK software breakpoint instruction to generate
a trap instead, similarly to most other arches, with the generic
BUG code generating the dmesg boilerplate.

This allows bug metadata to be moved to a separate table and
reduces the amount of inline code at BUG and WARN sites.  This also
avoids clobbering any registers before they can be dumped.

To mitigate the size of the bug table further, this patch makes
use of the existing infrastructure for encoding addresses within
the bug table as 32-bit offsets instead of absolute pointers.
(Note that this limits the kernel size to 2GB.)

Traps are registered at arch_initcall time for aarch64, but BUG
has minimal real dependencies and it is desirable to be able to
generate bug splats as early as possible.  This patch redirects
all debug exceptions caused by BRK directly to bug_handler() until
the full debug exception support has been initialised.

Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27 11:08:42 +01:00
..
cache.S arm64: mm: Adopt new alternative assembler macros 2015-07-27 11:08:40 +01:00
context.c arm64: force CONFIG_SMP=y and remove redundant #ifdefs 2015-07-27 11:08:40 +01:00
copypage.c arm64: export __cpu_{clear,copy}_user_page functions 2014-07-08 17:30:51 +01:00
dma-mapping.c arm64: dma-mapping: implement dma_get_sgtable() 2015-07-27 11:08:40 +01:00
dump.c arm64: mm: Fix build error with CONFIG_SPARSEMEM_VMEMMAP disabled 2015-05-05 12:22:17 +01:00
extable.c arm64: MMU fault handling and page table management 2012-09-17 13:41:57 +01:00
fault.c arm64/BUG: Use BRK instruction for generic BUG traps 2015-07-27 11:08:42 +01:00
flush.c arm64: force CONFIG_SMP=y and remove redundant #ifdefs 2015-07-27 11:08:40 +01:00
hugetlbpage.c arm64: hugetlb: remove paragraph about writing to FSF 2015-07-27 11:08:40 +01:00
init.c arm64: mm: Fix freeing of the wrong memmap entries with !SPARSEMEM_VMEMMAP 2015-06-17 14:29:34 +01:00
ioremap.c arm64: add ioremap physical address information 2015-01-23 15:29:06 +00:00
Makefile arm64: remove another unnecessary libfdt include path 2015-07-06 17:15:14 +01:00
mm.h arm64: add better page protections to arm64 2015-01-22 14:54:29 +00:00
mmap.c mm: expose arch_mmap_rnd when available 2015-04-14 16:49:05 -07:00
mmu.c arm64: remove dead code 2015-07-27 11:08:39 +01:00
pageattr.c arm64: mm: unexport set_memory_ro and set_memory_rw 2015-03-19 10:43:56 +00:00
pgd.c arm64: pgalloc: consistently use PGALLOC_GFP 2014-11-20 12:05:18 +00:00
proc-macros.S arm64: mm: increase VA range of identity map 2015-03-23 11:35:29 +00:00
proc.S arm64: force CONFIG_SMP=y and remove redundant #ifdefs 2015-07-27 11:08:40 +01:00