This is a note to let you know that I've just added the patch titled
mmc: meson-gx: remove redundant mmc_request_done() call from irq context
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
mmc-meson-gx-remove-redundant-mmc_request_done-call-.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 3ec73050704ec7d9f7659012445d9210aa478ebc
Author: Martin Hundebøll <martin@xxxxxxxxxx>
Date: Wed Jun 7 10:27:12 2023 +0200
mmc: meson-gx: remove redundant mmc_request_done() call from irq context
[ Upstream commit 3c40eb8145325b0f5b93b8a169146078cb2c49d6 ]
The call to mmc_request_done() can schedule, so it must not be called
from irq context. Wake the irq thread if it needs to be called, and let
its existing logic do its work.
Fixes the following kernel bug, which appears when running an RT patched
kernel on the AmLogic Meson AXG A113X SoC:
[ 11.111407] BUG: scheduling while atomic: kworker/0:1H/75/0x00010001
[ 11.111438] Modules linked in:
[ 11.111451] CPU: 0 PID: 75 Comm: kworker/0:1H Not tainted 6.4.0-rc3-rt2-rtx-00081-gfd07f41ed6b4-dirty #1
[ 11.111461] Hardware name: RTX AXG A113X Linux Platform Board (DT)
[ 11.111469] Workqueue: kblockd blk_mq_run_work_fn
[ 11.111492] Call trace:
[ 11.111497] dump_backtrace+0xac/0xe8
[ 11.111510] show_stack+0x18/0x28
[ 11.111518] dump_stack_lvl+0x48/0x60
[ 11.111530] dump_stack+0x18/0x24
[ 11.111537] __schedule_bug+0x4c/0x68
[ 11.111548] __schedule+0x80/0x574
[ 11.111558] schedule_loop+0x2c/0x50
[ 11.111567] schedule_rtlock+0x14/0x20
[ 11.111576] rtlock_slowlock_locked+0x468/0x730
[ 11.111587] rt_spin_lock+0x40/0x64
[ 11.111596] __wake_up_common_lock+0x5c/0xc4
[ 11.111610] __wake_up+0x18/0x24
[ 11.111620] mmc_blk_mq_req_done+0x68/0x138
[ 11.111633] mmc_request_done+0x104/0x118
[ 11.111644] meson_mmc_request_done+0x38/0x48
[ 11.111654] meson_mmc_irq+0x128/0x1f0
[ 11.111663] __handle_irq_event_percpu+0x70/0x114
[ 11.111674] handle_irq_event_percpu+0x18/0x4c
[ 11.111683] handle_irq_event+0x80/0xb8
[ 11.111691] handle_fasteoi_irq+0xa4/0x120
[ 11.111704] handle_irq_desc+0x20/0x38
[ 11.111712] generic_handle_domain_irq+0x1c/0x28
[ 11.111721] gic_handle_irq+0x8c/0xa8
[ 11.111735] call_on_irq_stack+0x24/0x4c
[ 11.111746] do_interrupt_handler+0x88/0x94
[ 11.111757] el1_interrupt+0x34/0x64
[ 11.111769] el1h_64_irq_handler+0x18/0x24
[ 11.111779] el1h_64_irq+0x64/0x68
[ 11.111786] __add_wait_queue+0x0/0x4c
[ 11.111795] mmc_blk_rw_wait+0x84/0x118
[ 11.111804] mmc_blk_mq_issue_rq+0x5c4/0x654
[ 11.111814] mmc_mq_queue_rq+0x194/0x214
[ 11.111822] blk_mq_dispatch_rq_list+0x3ac/0x528
[ 11.111834] __blk_mq_sched_dispatch_requests+0x340/0x4d0
[ 11.111847] blk_mq_sched_dispatch_requests+0x38/0x70
[ 11.111858] blk_mq_run_work_fn+0x3c/0x70
[ 11.111865] process_one_work+0x17c/0x1f0
[ 11.111876] worker_thread+0x1d4/0x26c
[ 11.111885] kthread+0xe4/0xf4
[ 11.111894] ret_from_fork+0x10/0x20
Fixes: 51c5d8447bd7 ("MMC: meson: initial support for GX platforms")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Martin Hundebøll <martin@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230607082713.517157-1-martin@xxxxxxxxxx
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/mmc/host/meson-gx-mmc.c b/drivers/mmc/host/meson-gx-mmc.c
index 313aff92b97c9..a3e5be81b4660 100644
--- a/drivers/mmc/host/meson-gx-mmc.c
+++ b/drivers/mmc/host/meson-gx-mmc.c
@@ -1067,11 +1067,8 @@ static irqreturn_t meson_mmc_irq(int irq, void *dev_id)
if (status & (IRQ_END_OF_CHAIN | IRQ_RESP_STATUS)) {
if (data && !cmd->error)
data->bytes_xfered = data->blksz * data->blocks;
- if (meson_mmc_bounce_buf_read(data) ||
- meson_mmc_get_next_command(cmd))
- ret = IRQ_WAKE_THREAD;
- else
- ret = IRQ_HANDLED;
+
+ return IRQ_WAKE_THREAD;
}
out:
@@ -1086,9 +1083,6 @@ static irqreturn_t meson_mmc_irq(int irq, void *dev_id)
writel(start, host->regs + SD_EMMC_START);
}
- if (ret == IRQ_HANDLED)
- meson_mmc_request_done(host->mmc, cmd->mrq);
-
return ret;
}
