From be9fa663d325a102de53c9ab6d00a31dcb36bb73 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Thu, 18 Jan 2018 16:33:57 -0800 Subject: scripts/decodecode: fix decoding for AArch64 (arm64) instructions There are a couple of problems with the decodecode script and arm64: 1. AArch64 objdump refuses to disassemble .4byte directives as instructions, insisting that they are data values and displaying them as: a94153f3 .word 0xa94153f3 <-- trapping instruction This is resolved by using the .inst directive instead. 2. Disassembly of branch instructions attempts to provide the target as an offset from a symbol, e.g.: 0: 34000082 cbz w2, 10 <.text+0x10> however this falls foul of the grep -v, which matches lines containing ".text" and ends up removing all branch instructions from the dump. This patch resolves both issues by using the .inst directive for 4-byte quantities on arm64 and stripping the resulting binaries (as is done on arm already) to remove the mapping symbols. Link: http://lkml.kernel.org/r/1506596147-23630-1-git-send-email-will.deacon@arm.com Signed-off-by: Will Deacon Reviewed-by: Dave Martin Cc: Michal Marek Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/decodecode | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'scripts') diff --git a/scripts/decodecode b/scripts/decodecode index 438120da1361..5ea071099330 100755 --- a/scripts/decodecode +++ b/scripts/decodecode @@ -59,6 +59,14 @@ disas() { ${CROSS_COMPILE}strip $1.o fi + if [ "$ARCH" = "arm64" ]; then + if [ $width -eq 4 ]; then + type=inst + fi + + ${CROSS_COMPILE}strip $1.o + fi + ${CROSS_COMPILE}objdump $OBJDUMPFLAGS -S $1.o | \ grep -v "/tmp\|Disassembly\|\.text\|^$" > $1.dis 2>&1 } -- cgit v1.2.3-59-g8ed1b