4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Martin Hundebøll <martin@xxxxxxxxxx> [ 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> --- 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 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; } -- 2.40.1