diff options
| author | Will Deacon <will@kernel.org> | 2024-05-02 10:37:23 +0100 |
|---|---|---|
| committer | Christoph Hellwig <hch@lst.de> | 2024-05-02 14:57:04 +0200 |
| commit | 75961ffb5cb3e5196f19cae7683f35cc88b50800 (patch) | |
| tree | 20e179fa900685e7ca35bf5c58e1ce35a95fbf2f /kernel | |
| parent | e67572cd2204894179d89bd7b984072f19313b03 (diff) | |
| download | linux-75961ffb5cb3e5196f19cae7683f35cc88b50800.tar.gz | |
swiotlb: initialise restricted pool list_head when SWIOTLB_DYNAMIC=y
Using restricted DMA pools (CONFIG_DMA_RESTRICTED_POOL=y) in conjunction
with dynamic SWIOTLB (CONFIG_SWIOTLB_DYNAMIC=y) leads to the following
crash when initialising the restricted pools at boot-time:
| Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008
| Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP
| pc : rmem_swiotlb_device_init+0xfc/0x1ec
| lr : rmem_swiotlb_device_init+0xf0/0x1ec
| Call trace:
| rmem_swiotlb_device_init+0xfc/0x1ec
| of_reserved_mem_device_init_by_idx+0x18c/0x238
| of_dma_configure_id+0x31c/0x33c
| platform_dma_configure+0x34/0x80
faddr2line reveals that the crash is in the list validation code:
include/linux/list.h:83
include/linux/rculist.h:79
include/linux/rculist.h:106
kernel/dma/swiotlb.c:306
kernel/dma/swiotlb.c:1695
because add_mem_pool() is trying to list_add_rcu() to a NULL
'mem->pools'.
Fix the crash by initialising the 'mem->pools' list_head in
rmem_swiotlb_device_init() before calling add_mem_pool().
Reported-by: Nikita Ioffe <ioffe@google.com>
Tested-by: Nikita Ioffe <ioffe@google.com>
Fixes: 1aaa736815eb ("swiotlb: allocate a new memory pool when existing pools are full")
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/dma/swiotlb.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index a5e0dfc44d24e..0de66f0ff43ab 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -1798,6 +1798,7 @@ static int rmem_swiotlb_device_init(struct reserved_mem *rmem, mem->for_alloc = true; #ifdef CONFIG_SWIOTLB_DYNAMIC spin_lock_init(&mem->lock); + INIT_LIST_HEAD_RCU(&mem->pools); #endif add_mem_pool(mem, pool); |