kernel.git/arch/arm64/kernel/kgdb.c, branch linux-4.7.y

arm64: kgdb: Match pstate size with gdbserver protocol

2016-06-16T18:20:51Z

Current versions of gdb do not interoperate cleanly with kgdb on arm64 systems because gdb and kgdb do not use the same register description. This patch modifies kgdb to work with recent releases of gdb (>= 7.8.1). Compatibility with gdb (after the patch is applied) is as follows: gdb-7.6 and earlier Ok gdb-7.7 series Works if user provides custom target description gdb-7.8(.0) Works if user provides custom target description gdb-7.8.1 and later Ok When commit 44679a4f142b ("arm64: KGDB: Add step debugging support") was introduced it was paired with a gdb patch that made an incompatible change to the gdbserver protocol. This patch was eventually merged into the gdb sources: https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;a=commit;h=a4d9ba85ec5597a6a556afe26b712e878374b9dd The change to the protocol was mostly made to simplify big-endian support inside the kernel gdb stub. Unfortunately the gdb project released gdb-7.7.x and gdb-7.8.0 before the protocol incompatibility was identified and reversed: https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;a=commit;h=bdc144174bcb11e808b4e73089b850cf9620a7ee This leaves us in a position where kgdb still uses the no-longer-used protocol; gdb-7.8.1, which restored the original behaviour, was released on 2014-10-29. I don't believe it is possible to detect/correct the protocol incompatiblity which means the kernel must take a view about which version of the gdb remote protocol is "correct". This patch takes the view that the original/current version of the protocol is correct and that version found in gdb-7.7.x and gdb-7.8.0 is anomalous. Signed-off-by: Daniel Thompson Signed-off-by: Will Deacon

arm64: Fix misspellings in comments.

2016-03-04T18:19:17Z

Signed-off-by: Adam Buchbinder Signed-off-by: Catalin Marinas

arm64/debug: Simplify BRK insn opcode declarations

2015-07-27T10:08:42Z

The way the KGDB_DYN_BRK_INS_BYTEx macros are declared is more complex than it needs to be. Also, the macros are only used in one place, which is arch-specific anyway. This patch refactors the macros to simplify them, and exposes an argument so that we can have a single macro instead of 4. As a side effect, this patch also fixes some anomalous spellings of "KGDB". These changes alter the compile types of some integer constants that are harmless but trigger truncation warnings in gcc when assigning to 32-bit variables. This patch adds an explicit cast for the affected cases. Signed-off-by: Dave Martin Signed-off-by: Will Deacon

arm64/debug: More consistent naming for the BRK ESR template macro

2015-07-27T10:08:42Z

The naming of DBG_ESR_VAL_BRK is inconsistent with the way other similar macros are named. This patch makes the naming more consistent, and appends "64" as a reminder that this ESR pattern only matches from AArch64 state. Signed-off-by: Dave Martin Acked-by: Mark Rutland Acked-by: Catalin Marinas Signed-off-by: Will Deacon

arm64: Fix typos in KGDB macros

2014-09-25T14:35:41Z

Some of the KGDB macros used for generating the BRK instructions had the wrong spelling for DBG and KGDB abbreviations. Signed-off-by: Catalin Marinas

arm64: KGDB: Add step debugging support

2014-02-26T11:16:25Z

Add KGDB software step debugging support for EL1 debug in AArch64 mode. KGDB registers step debug handler with debug monitor. On receiving 'step' command from GDB tool, target enables software step debugging and step address is updated in ELR. Software Step debugging is disabled when 'continue' command is received Signed-off-by: Vijaya Kumar K Reviewed-by: Will Deacon Signed-off-by: Catalin Marinas

arm64: KGDB: Add Basic KGDB support

2014-02-26T11:16:25Z

Add KGDB debug support for kernel debugging. With this patch, basic KGDB debugging is possible.GDB register layout is updated and GDB tool can establish connection with target and can set/clear breakpoints. Signed-off-by: Vijaya Kumar K Reviewed-by: Will Deacon Signed-off-by: Catalin Marinas