diff options
| author | Xie Yuanbin <xieyuanbin1@huawei.com> | 2026-07-28 03:03:22 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@armlinux.org.uk> | 2026-08-05 16:15:13 +0100 |
| commit | e79ca91165d4fd18549c536abdb86101e889052f (patch) | |
| tree | 376632c034b2dee1fe115a3e0884e09494b793e0 | |
| parent | 8a58a41100ea377e978d99600ec24a9bd0273662 (diff) | |
| download | linux-e79ca91165d4fd18549c536abdb86101e889052f.tar.gz linux-e79ca91165d4fd18549c536abdb86101e889052f.zip | |
ARM: 9484/1: enable interrupts when unhandled user faults are triggered
PREEMPT_RT requires interrupts to be enabled when sending signals.
When do_DataAbort()/do_PrefetchAbort() triggers unhandled user faults,
that is `inf->fn()` return a non-zero value, and the interrupts are not
enabled within the hook function, force_sig_fault() will be called
with interrupts disabled.
This can be triggered by user programs executing the bkpt instruction,
with kernel config CONFIG_PERF_EVENTS=n.
Enable interrupts in do_DataAbort()/do_PrefetchAbort() when unhandled
user faults are triggered to fix the issue.
Fixes: c6e61c06d606 ("ARM: 9463/1: Allow to enable RT")
Link: https://lore.kernel.org/20260629123349.134224-1-xieyuanbin1@huawei.com
Suggested-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Linus Walleij <linusw@kernel.org>
Signed-off-by: Xie Yuanbin <xieyuanbin1@huawei.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
| -rw-r--r-- | arch/arm/mm/fault.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c index e62cc4be5adf..c68677503532 100644 --- a/arch/arm/mm/fault.c +++ b/arch/arm/mm/fault.c @@ -633,6 +633,9 @@ do_DataAbort(unsigned long addr, unsigned int fsr, struct pt_regs *regs) if (!inf->fn(addr, fsr & ~FSR_LNX_PF, regs)) return; + if (likely(user_mode(regs))) + local_irq_enable(); + pr_alert("8<--- cut here ---\n"); pr_alert("Unhandled fault: %s (0x%03x) at 0x%08lx\n", inf->name, fsr, addr); @@ -663,6 +666,9 @@ do_PrefetchAbort(unsigned long addr, unsigned int ifsr, struct pt_regs *regs) if (!inf->fn(addr, ifsr | FSR_LNX_PF, regs)) return; + if (likely(user_mode(regs))) + local_irq_enable(); + pr_alert("8<--- cut here ---\n"); pr_alert("Unhandled prefetch abort: %s (0x%03x) at 0x%08lx\n", inf->name, ifsr, addr); |