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: [email protected]
Signed-off-by: Martin Hundebøll <[email protected]>
---
Version 1 of this patch:
https://lore.kernel.org/linux-amlogic/[email protected]/
Changes since v1:
* remove redundant change to meson_mmc_irq_thread(), as per Martin's
review
* return early instead of assigning to "ret" variable
* change commit short-log to reflect code removal instead of it being
moved. (Was: "mmc: meson: move mmc_request_done() call to irq thread")
drivers/mmc/host/meson-gx-mmc.c | 10 ++--------
1 file changed, 2 insertions(+), 8 deletions(-)
diff --git a/drivers/mmc/host/meson-gx-mmc.c b/drivers/mmc/host/meson-gx-mmc.c
index b8514d9d5e736..f90b0fd8d8b00 100644
--- a/drivers/mmc/host/meson-gx-mmc.c
+++ b/drivers/mmc/host/meson-gx-mmc.c
@@ -991,11 +991,8 @@ static irqreturn_t meson_mmc_irq(int irq, void *dev_id)
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:
@@ -1007,9 +1004,6 @@ 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;
}
--
2.40.1
On Wed, 7 Jun 2023 at 10:27, Martin Hundebøll <[email protected]> wrote:
>
> 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: [email protected]
> Signed-off-by: Martin Hundebøll <[email protected]>
Applied for fixes, thanks!
Kind regards
Uffe
> ---
> Version 1 of this patch:
> https://lore.kernel.org/linux-amlogic/[email protected]/
>
> Changes since v1:
> * remove redundant change to meson_mmc_irq_thread(), as per Martin's
> review
> * return early instead of assigning to "ret" variable
> * change commit short-log to reflect code removal instead of it being
> moved. (Was: "mmc: meson: move mmc_request_done() call to irq thread")
>
> drivers/mmc/host/meson-gx-mmc.c | 10 ++--------
> 1 file changed, 2 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/mmc/host/meson-gx-mmc.c b/drivers/mmc/host/meson-gx-mmc.c
> index b8514d9d5e736..f90b0fd8d8b00 100644
> --- a/drivers/mmc/host/meson-gx-mmc.c
> +++ b/drivers/mmc/host/meson-gx-mmc.c
> @@ -991,11 +991,8 @@ static irqreturn_t meson_mmc_irq(int irq, void *dev_id)
>
> 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:
> @@ -1007,9 +1004,6 @@ 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;
> }
>
> --
> 2.40.1
>