kernel/linux.git/include/linux/rseq.h, branch v6.12.80Linux kernel stable tree (mirror)https://git.radix-linux.su/kernel/linux.git/atom?h=v6.12.802025-10-19T14:33:34+00:00rseq: Protect event mask against membarrier IPI2025-10-19T14:33:34+00:00Thomas Gleixnertglx@linutronix.de2025-08-13T15:02:30+00:00urn:sha1:b42a82c630f407e3b4eddd24d460c5ce45cd547e
commit 6eb350a2233100a283f882c023e5ad426d0ed63b upstream.
rseq_need_restart() reads and clears task::rseq_event_mask with preemption
disabled to guard against the scheduler.
But membarrier() uses an IPI and sets the PREEMPT bit in the event mask
from the IPI, which leaves that RMW operation unprotected.
Use guard(irq) if CONFIG_MEMBARRIER is enabled to fix that.
Fixes: 2a36ab717e8f ("rseq/membarrier: Add MEMBARRIER_CMD_PRIVATE_EXPEDITED_RSEQ")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
rseq: Split out rseq.h from sched.h2023-12-27T16:49:56+00:00Kent Overstreetkent.overstreet@linux.dev2023-12-15T20:58:20+00:00urn:sha1:932562a6045ed613d45bd100db37114273c22077
We're trying to get sched.h down to more or less just types only, not
code - rseq can live in its own header.
This helps us kill the dependency on preempt.h in sched.h.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>