Richard Genoud 014077044e soc: fsl: qbman: fix race condition in qman_destroy_fq ... When QMAN_FQ_FLAG_DYNAMIC_FQID is set, there's a race condition between fq_table[fq->idx] state and freeing/allocating from the pool and WARN_ON(fq_table[fq->idx]) in qman_create_fq() gets triggered. Indeed, we can have: Thread A Thread B qman_destroy_fq() qman_create_fq() qman_release_fqid() qman_shutdown_fq() gen_pool_free() -- At this point, the fqid is available again -- qman_alloc_fqid() -- so, we can get the just-freed fqid in thread B -- fq->fqid = fqid; fq->idx = fqid * 2; WARN_ON(fq_table[fq->idx]); fq_table[fq->idx] = fq; fq_table[fq->idx] = NULL; And adding some logs between qman_release_fqid() and fq_table[fq->idx] = NULL makes the WARN_ON() trigger a lot more. To prevent that, ensure that fq_table[fq->idx] is set to NULL before gen_pool_free() is called by using smp_wmb(). Fixes: c535e923bb ("soc/fsl: Introduce DPAA 1.x QMan device driver") Signed-off-by: Richard Genoud <richard.genoud@bootlin.com> Tested-by: CHAMPSEIX Thomas <thomas.champseix@alstomgroup.com> Link: https://lore.kernel.org/r/20251223072549.397625-1-richard.genoud@bootlin.com Signed-off-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>		2026-02-23 14:49:27 +01:00
..
bman_ccsr.c	soc: fsl: qbman: Remove RESERVEDMEM_OF_DECLARE usage	2024-03-06 18:30:59 -06:00
bman_portal.c
bman_priv.h
bman_test_api.c
bman_test.c
bman_test.h
bman.c	Convert 'alloc_obj' family to use the new default GFP_KERNEL argument	2026-02-21 17:09:51 -08:00
dpaa_sys.c	soc: fsl: qbman: Remove RESERVEDMEM_OF_DECLARE usage	2024-03-06 18:30:59 -06:00
dpaa_sys.h	soc: fsl: qbman: Remove RESERVEDMEM_OF_DECLARE usage	2024-03-06 18:30:59 -06:00
Kconfig	soc: fsl: qbman: FSL_DPAA depends on COMPILE_TEST	2024-07-14 20:26:16 -07:00
Makefile
qman_ccsr.c	soc: fsl: qbman: Remove redundant warnings	2024-09-03 07:50:57 +02:00
qman_portal.c	soc: fsl: qbman: Use iommu_paging_domain_alloc()	2024-09-03 07:50:57 +02:00
qman_priv.h
qman_test_api.c
qman_test_stash.c	soc: fsl: qbman: use kmalloc_array() instead of kmalloc()	2025-11-26 12:29:40 +01:00
qman_test.c
qman_test.h
qman.c	soc: fsl: qbman: fix race condition in qman_destroy_fq	2026-02-23 14:49:27 +01:00