arm64: Allow hw watchpoint at varied offset from base address
authorPratyush Anand <panand@redhat.com>
Mon, 14 Nov 2016 14:02:43 +0000 (19:32 +0530)
committerWill Deacon <will.deacon@arm.com>
Fri, 18 Nov 2016 17:23:17 +0000 (17:23 +0000)
commitb08fb180bb8802d1c599beb1acd6a3b26163b4f6
tree6bac18ec10002380cb5a3ed70d8cc706733d60f6
parent651be3cb085341a21847e47c694c249c3e1e4e5b
arm64: Allow hw watchpoint at varied offset from base address

ARM64 hardware supports watchpoint at any double word aligned address.
However, it can select any consecutive bytes from offset 0 to 7 from that
base address. For example, if base address is programmed as 0x420030 and
byte select is 0x1C, then access of 0x420032,0x420033 and 0x420034 will
generate a watchpoint exception.

Currently, we do not have such modularity. We can only program byte,
halfword, word and double word access exception from any base address.

This patch adds support to overcome above limitations.

Signed-off-by: Pratyush Anand <panand@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
arch/arm64/include/asm/hw_breakpoint.h
arch/arm64/kernel/hw_breakpoint.c
arch/arm64/kernel/ptrace.c