On 9/2/20 1:29 AM, Ravi Bangoria wrote:
Patch #1 fixes issue for quardword instruction on p10 predecessors.
Patch #2 fixes issue for vector instructions.
Patch #3 fixes a bug about watchpoint not firing when created with
ptrace PPC_PTRACE_SETHWDEBUG and CONFIG_HAVE_HW_BREAKPOINT=N.
The fix uses HW_BRK_TYPE_PRIV_ALL for ptrace user which, I
guess, should be fine because we don't leak any kernel
addresses and PRIV_ALL will also help to cover scenarios when
kernel accesses user memory.
Patch #4,#5 fixes infinite exception bug, again the bug happens only
with CONFIG_HAVE_HW_BREAKPOINT=N.
Patch #6 fixes two places where we are missing to set hw_len.
Patch #7 introduce new feature bit PPC_DEBUG_FEATURE_DATA_BP_ARCH_31
which will be set when running on ISA 3.1 compliant machine.
Patch #8 finally adds selftest to test scenarios fixed by patch#2,#3
and also moves MODE_EXACT tests outside of BP_RANGE condition.
Christophe, let me know if this series breaks something for 8xx.
v5:
https://lore.kernel.org/r/20200825043617.1073634-1-ravi.bango...@linux.ibm.com
v5->v6:
- Fix build faulure reported by kernel test robot
- patch #5. Use more compact if condition, suggested by Christophe
Ravi Bangoria (8):
powerpc/watchpoint: Fix quarword instruction handling on p10
predecessors
powerpc/watchpoint: Fix handling of vector instructions
powerpc/watchpoint/ptrace: Fix SETHWDEBUG when
CONFIG_HAVE_HW_BREAKPOINT=N
powerpc/watchpoint: Move DAWR detection logic outside of
hw_breakpoint.c
powerpc/watchpoint: Fix exception handling for
CONFIG_HAVE_HW_BREAKPOINT=N
powerpc/watchpoint: Add hw_len wherever missing
powerpc/watchpoint/ptrace: Introduce PPC_DEBUG_FEATURE_DATA_BP_ARCH_31
powerpc/watchpoint/selftests: Tests for kernel accessing user memory
Documentation/powerpc/ptrace.rst | 1 +
arch/powerpc/include/asm/hw_breakpoint.h | 12 ++
arch/powerpc/include/uapi/asm/ptrace.h | 1 +
arch/powerpc/kernel/Makefile | 3 +-
arch/powerpc/kernel/hw_breakpoint.c | 149 +---------------
.../kernel/hw_breakpoint_constraints.c | 162 ++++++++++++++++++
arch/powerpc/kernel/process.c | 48 ++++++
arch/powerpc/kernel/ptrace/ptrace-noadv.c | 9 +-
arch/powerpc/xmon/xmon.c | 1 +
.../selftests/powerpc/ptrace/ptrace-hwbreak.c | 48 +++++-
10 files changed, 282 insertions(+), 152 deletions(-)
create mode 100644 arch/powerpc/kernel/hw_breakpoint_constraints.c
Tested this patch set for:
- SETHWDEBUG when CONFIG_HAVE_HW_BREAKPOINT=N = OK
- Fix exception handling for CONFIG_HAVE_HW_BREAKPOINT=N = OK
- Check for PPC_DEBUG_FEATURE_DATA_BP_ARCH_31 = OK
- Fix quarword instruction handling on p10 predecessors = OK
- Fix handling of vector instructions = OK
Also tested for:
- Set second watchpoint (P10 Mambo) = OK
- Infinity loop on sc instruction = OK
