6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx>
[ Upstream commit 3892b11eac5aaaeefbf717f1953288b77759d9e2 ]
Currently, there are some places to set CSR.PRMD.PWE, the first one is
in hw_breakpoint_thread_switch() to enable user space singlestep via
checking TIF_SINGLESTEP, the second one is in hw_breakpoint_control() to
enable user space watchpoint. For the latter case, it should also check
TIF_LOAD_WATCH to make the logic correct and clear.
Fixes: c8e57ab0995c ("LoongArch: Trigger user-space watchpoints correctly")
Signed-off-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx>
Signed-off-by: Huacai Chen <chenhuacai@xxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/loongarch/kernel/hw_breakpoint.c | 2 +-
arch/loongarch/kernel/ptrace.c | 3 +++
2 files changed, 4 insertions(+), 1 deletion(-)
diff --git a/arch/loongarch/kernel/hw_breakpoint.c b/arch/loongarch/kernel/hw_breakpoint.c
index 621ad7634df71..a6e4b605bfa8d 100644
--- a/arch/loongarch/kernel/hw_breakpoint.c
+++ b/arch/loongarch/kernel/hw_breakpoint.c
@@ -221,7 +221,7 @@ static int hw_breakpoint_control(struct perf_event *bp,
}
enable = csr_read64(LOONGARCH_CSR_CRMD);
csr_write64(CSR_CRMD_WE | enable, LOONGARCH_CSR_CRMD);
- if (bp->hw.target)
+ if (bp->hw.target && test_tsk_thread_flag(bp->hw.target, TIF_LOAD_WATCH))
regs->csr_prmd |= CSR_PRMD_PWE;
break;
case HW_BREAKPOINT_UNINSTALL:
diff --git a/arch/loongarch/kernel/ptrace.c b/arch/loongarch/kernel/ptrace.c
index 200109de1971a..19dc6eff45ccc 100644
--- a/arch/loongarch/kernel/ptrace.c
+++ b/arch/loongarch/kernel/ptrace.c
@@ -589,6 +589,7 @@ static int ptrace_hbp_set_ctrl(unsigned int note_type,
struct perf_event *bp;
struct perf_event_attr attr;
struct arch_hw_breakpoint_ctrl ctrl;
+ struct thread_info *ti = task_thread_info(tsk);
bp = ptrace_hbp_get_initialised_bp(note_type, tsk, idx);
if (IS_ERR(bp))
@@ -613,8 +614,10 @@ static int ptrace_hbp_set_ctrl(unsigned int note_type,
if (err)
return err;
attr.disabled = 0;
+ set_ti_thread_flag(ti, TIF_LOAD_WATCH);
} else {
attr.disabled = 1;
+ clear_ti_thread_flag(ti, TIF_LOAD_WATCH);
}
return modify_user_hw_breakpoint(bp, &attr);
--
2.43.0
