| Message ID | 1701929559-18252-1-git-send-email-quic_mojha@quicinc.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | irqchip/gic-v3-its: BUG_ON if stall bit is set | expand |
On Thu, 07 Dec 2023 06:12:39 +0000, Mukesh Ojha <quic_mojha@quicinc.com> wrote: > > There could be various reason that stall bit could > be set due to software errors while processing > commands in command queue is being processed and Such as? > waiting for 1s is not going to help in debugging > as command processing anyways going to be timed > out and system will continue to run and may crash > after some time due to this. > > So, to debug such issues what command caused the > stall bit to set, BUG_ON right away. How on Earth will killing the system allow *anything* to be further debugged? If you need debug information, add the correct debug statements using pr_debug(). Even better, try to gracefully recover from it if the ITS command queue supports restarting. Crashing the system is not an option. M.
diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c index 9a7a74239eab..8983e0a3318c 100644 --- a/drivers/irqchip/irq-gic-v3-its.c +++ b/drivers/irqchip/irq-gic-v3-its.c @@ -1078,6 +1078,11 @@ static int its_wait_for_range_completion(struct its_node *its, s64 delta; rd_idx = readl_relaxed(its->base + GITS_CREADR); + /* + * Check for stall bit as there is no point in waiting + * for 1s if the stall bit is already set. + */ + BUG_ON(rd_idx & 1); /* * Compute the read pointer progress, taking the
There could be various reason that stall bit could be set due to software errors while processing commands in command queue is being processed and waiting for 1s is not going to help in debugging as command processing anyways going to be timed out and system will continue to run and may crash after some time due to this. So, to debug such issues what command caused the stall bit to set, BUG_ON right away. Signed-off-by: Mukesh Ojha <quic_mojha@quicinc.com> --- drivers/irqchip/irq-gic-v3-its.c | 5 +++++ 1 file changed, 5 insertions(+)