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Zhu Yanjun 84bb006408 RDMA/rxe: Fix soft lockup problem due to using tasklets in softirq ... commit 8ac0e6641c upstream. When run stress tests with RXE, the following Call Traces often occur watchdog: BUG: soft lockup - CPU#2 stuck for 22s! [swapper/2:0] ... Call Trace: <IRQ> create_object+0x3f/0x3b0 kmem_cache_alloc_node_trace+0x129/0x2d0 __kmalloc_reserve.isra.52+0x2e/0x80 __alloc_skb+0x83/0x270 rxe_init_packet+0x99/0x150 [rdma_rxe] rxe_requester+0x34e/0x11a0 [rdma_rxe] rxe_do_task+0x85/0xf0 [rdma_rxe] tasklet_action_common.isra.21+0xeb/0x100 __do_softirq+0xd0/0x298 irq_exit+0xc5/0xd0 smp_apic_timer_interrupt+0x68/0x120 apic_timer_interrupt+0xf/0x20 </IRQ> ... The root cause is that tasklet is actually a softirq. In a tasklet handler, another softirq handler is triggered. Usually these softirq handlers run on the same cpu core. So this will cause "soft lockup Bug". Fixes: 8700e3e7c4 ("Soft RoCE driver") Link: https://lore.kernel.org/r/20200212072635.682689-8-leon@kernel.org Signed-off-by: Zhu Yanjun <yanjunz@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		History 2020-02-19 19:54:09 +01:00
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rdmavt	IB/rdmavt: Reset all QPs when the device is shut down	2020-02-19 19:54:08 +01:00
rxe	RDMA/rxe: Fix soft lockup problem due to using tasklets in softirq	2020-02-19 19:54:09 +01:00
siw	RDMA subsystem updates for 5.5	2019-11-27 10:17:28 -08:00
Makefile	rdma/siw: addition to kernel build environment	2019-07-02 17:03:41 -03:00