6.1-stable review patch. If anyone has any objections, please let me know.
------------------
From: Saeed Mahameed saeedm@nvidia.com
commit 314ded538e5f22e7610b1bf621402024a180ec80 upstream.
The kernel IRQ system needs the irq affinity notifier to be clear before attempting to free the irq, see WARN_ON log below.
On a normal driver unload we don't have this issue since we do the complete cleanup of the irq resources.
To fix this, put the important resources cleanup in a helper function and use it in both normal driver unload and shutdown flows.
[ 4497.498434] ------------[ cut here ]------------ [ 4497.498726] WARNING: CPU: 0 PID: 9 at kernel/irq/manage.c:2034 free_irq+0x295/0x340 [ 4497.499193] Modules linked in: [ 4497.499386] CPU: 0 PID: 9 Comm: kworker/0:1 Tainted: G W 6.4.0-rc4+ #10 [ 4497.499876] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-1.fc38 04/01/2014 [ 4497.500518] Workqueue: events do_poweroff [ 4497.500849] RIP: 0010:free_irq+0x295/0x340 [ 4497.501132] Code: 85 c0 0f 84 1d ff ff ff 48 89 ef ff d0 0f 1f 00 e9 10 ff ff ff 0f 0b e9 72 ff ff ff 49 8d 7f 28 ff d0 0f 1f 00 e9 df fd ff ff <0f> 0b 48 c7 80 c0 008 [ 4497.502269] RSP: 0018:ffffc90000053da0 EFLAGS: 00010282 [ 4497.502589] RAX: ffff888100949600 RBX: ffff88810330b948 RCX: 0000000000000000 [ 4497.503035] RDX: ffff888100949600 RSI: ffff888100400490 RDI: 0000000000000023 [ 4497.503472] RBP: ffff88810330c7e0 R08: ffff8881004005d0 R09: ffffffff8273a260 [ 4497.503923] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8881009ae000 [ 4497.504359] R13: ffff8881009ae148 R14: 0000000000000000 R15: ffff888100949600 [ 4497.504804] FS: 0000000000000000(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000 [ 4497.505302] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 4497.505671] CR2: 00007fce98806298 CR3: 000000000262e005 CR4: 0000000000370ef0 [ 4497.506104] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 4497.506540] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 4497.507002] Call Trace: [ 4497.507158] <TASK> [ 4497.507299] ? free_irq+0x295/0x340 [ 4497.507522] ? __warn+0x7c/0x130 [ 4497.507740] ? free_irq+0x295/0x340 [ 4497.507963] ? report_bug+0x171/0x1a0 [ 4497.508197] ? handle_bug+0x3c/0x70 [ 4497.508417] ? exc_invalid_op+0x17/0x70 [ 4497.508662] ? asm_exc_invalid_op+0x1a/0x20 [ 4497.508926] ? free_irq+0x295/0x340 [ 4497.509146] mlx5_irq_pool_free_irqs+0x48/0x90 [ 4497.509421] mlx5_irq_table_free_irqs+0x38/0x50 [ 4497.509714] mlx5_core_eq_free_irqs+0x27/0x40 [ 4497.509984] shutdown+0x7b/0x100 [ 4497.510184] pci_device_shutdown+0x30/0x60 [ 4497.510440] device_shutdown+0x14d/0x240 [ 4497.510698] kernel_power_off+0x30/0x70 [ 4497.510938] process_one_work+0x1e6/0x3e0 [ 4497.511183] worker_thread+0x49/0x3b0 [ 4497.511407] ? __pfx_worker_thread+0x10/0x10 [ 4497.511679] kthread+0xe0/0x110 [ 4497.511879] ? __pfx_kthread+0x10/0x10 [ 4497.512114] ret_from_fork+0x29/0x50 [ 4497.512342] </TASK>
Fixes: 9c2d08010963 ("net/mlx5: Free irqs only on shutdown callback") Signed-off-by: Saeed Mahameed saeedm@nvidia.com Reviewed-by: Shay Drory shayd@nvidia.com Signed-off-by: Mathieu Tortuyaux mtortuyaux@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/ethernet/mellanox/mlx5/core/pci_irq.c | 26 ++++++++++++++++------ 1 file changed, 20 insertions(+), 6 deletions(-)
--- a/drivers/net/ethernet/mellanox/mlx5/core/pci_irq.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/pci_irq.c @@ -123,18 +123,32 @@ out: return ret; }
-static void irq_release(struct mlx5_irq *irq) +/* mlx5_system_free_irq - Free an IRQ + * @irq: IRQ to free + * + * Free the IRQ and other resources such as rmap from the system. + * BUT doesn't free or remove reference from mlx5. + * This function is very important for the shutdown flow, where we need to + * cleanup system resoruces but keep mlx5 objects alive, + * see mlx5_irq_table_free_irqs(). + */ +static void mlx5_system_free_irq(struct mlx5_irq *irq) { - struct mlx5_irq_pool *pool = irq->pool; - - xa_erase(&pool->irqs, irq->index); /* free_irq requires that affinity_hint and rmap will be cleared * before calling it. This is why there is asymmetry with set_rmap * which should be called after alloc_irq but before request_irq. */ irq_update_affinity_hint(irq->irqn, NULL); - free_cpumask_var(irq->mask); free_irq(irq->irqn, &irq->nh); +} + +static void irq_release(struct mlx5_irq *irq) +{ + struct mlx5_irq_pool *pool = irq->pool; + + xa_erase(&pool->irqs, irq->index); + mlx5_system_free_irq(irq); + free_cpumask_var(irq->mask); kfree(irq); }
@@ -597,7 +611,7 @@ static void mlx5_irq_pool_free_irqs(stru unsigned long index;
xa_for_each(&pool->irqs, index, irq) - free_irq(irq->irqn, &irq->nh); + mlx5_system_free_irq(irq); }
static void mlx5_irq_pools_free_irqs(struct mlx5_irq_table *table)