6.6-stable review patch. If anyone has any objections, please let me know.
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From: Tiezhu Yang yangtiezhu@loongson.cn
[ 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@loongson.cn Signed-off-by: Huacai Chen chenhuacai@loongson.cn Signed-off-by: Sasha Levin sashal@kernel.org --- 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);