On 11/23/20 10:21 AM, Sai Prakash Ranjan wrote:
From: Mao Jinlong <jinlmao@xxxxxxxxxxxxxx> alloc_pages_node() return should be checked before calling dma_map_page() to make sure that valid page is mapped or else it can lead to aborts as below: Unable to handle kernel paging request at virtual address ffffffc008000000 Mem abort info: <snip>... pc : __dma_inv_area+0x40/0x58 lr : dma_direct_map_page+0xd8/0x1c8 Call trace: __dma_inv_area tmc_pages_alloc tmc_alloc_data_pages tmc_alloc_sg_table tmc_init_etr_sg_table tmc_alloc_etr_buf tmc_enable_etr_sink_sysfs tmc_enable_etr_sink coresight_enable_path coresight_enable enable_source_store dev_attr_store sysfs_kf_write Fixes: 99443ea19e8b ("coresight: Add generic TMC sg table framework") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Mao Jinlong <jinlmao@xxxxxxxxxxxxxx> Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@xxxxxxxxxxxxxx>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
--- drivers/hwtracing/coresight/coresight-tmc-etr.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c index 525f0ecc129c..a31a4d7ae25e 100644 --- a/drivers/hwtracing/coresight/coresight-tmc-etr.c +++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c @@ -217,6 +217,8 @@ static int tmc_pages_alloc(struct tmc_pages *tmc_pages, } else { page = alloc_pages_node(node, GFP_KERNEL | __GFP_ZERO, 0); + if (!page) + goto err; } paddr = dma_map_page(real_dev, page, 0, PAGE_SIZE, dir); if (dma_mapping_error(real_dev, paddr)) base-commit: c04e5d7bbf6f92a346d6b36770705e7f034df42d