diff options
author | Martin Sperl <kernel@martin.sperl.org> | 2015-05-10 07:50:45 +0000 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-07-21 10:10:13 -0700 |
commit | 2338b658b6eac40afdd6902f01b2bba9f8570d32 (patch) | |
tree | 97903a18d3125df65b8b40cef8a583beee61f62a | |
parent | 7012248100a1203f9936d6eab7b1d78e0f569218 (diff) |
spi: fix race freeing dummy_tx/rx before it is unmapped
commit 8e76ef88f607174082023f50b87fe12dcdbe5db5 upstream.
Fix a race (with some kernel configurations) where a queued
master->pump_messages runs and frees dummy_tx/rx before
spi_unmap_msg is running (or is finished).
This results in the following messages:
BUG: Bad page state in process
page:db7ba030 count:0 mapcount:0 mapping: (null) index:0x0
flags: 0x200(arch_1)
page dumped because: PAGE_FLAGS_CHECK_AT_PREP flag set
...
Reported-by: Noralf Trønnes <noralf@tronnes.org>
Suggested-by: Noralf Trønnes <noralf@tronnes.org>
Tested-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/spi/spi.c | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 57a195041dc7..75d6e99ac706 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -1091,9 +1091,6 @@ void spi_finalize_current_message(struct spi_master *master) spin_lock_irqsave(&master->queue_lock, flags); mesg = master->cur_msg; - master->cur_msg = NULL; - - queue_kthread_work(&master->kworker, &master->pump_messages); spin_unlock_irqrestore(&master->queue_lock, flags); spi_unmap_msg(master, mesg); @@ -1106,9 +1103,13 @@ void spi_finalize_current_message(struct spi_master *master) } } - trace_spi_message_done(mesg); - + spin_lock_irqsave(&master->queue_lock, flags); + master->cur_msg = NULL; master->cur_msg_prepared = false; + queue_kthread_work(&master->kworker, &master->pump_messages); + spin_unlock_irqrestore(&master->queue_lock, flags); + + trace_spi_message_done(mesg); mesg->state = NULL; if (mesg->complete) |