2020-11-23 10:23:36

by Sai Prakash Ranjan

Subject: [PATCH] coresight: tmc-etr: Check if page is valid before dma_map_page()

From: Mao Jinlong <[email protected]>

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: [email protected]
Signed-off-by: Mao Jinlong <[email protected]>
Signed-off-by: Sai Prakash Ranjan <[email protected]>
---
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
--
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation

2020-11-23 10:49:36

by Suzuki K Poulose

Subject: Re: [PATCH] coresight: tmc-etr: Check if page is valid before dma_map_page()

On 11/23/20 10:21 AM, Sai Prakash Ranjan wrote:
> From: Mao Jinlong <[email protected]>
>
> 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: [email protected]
> Signed-off-by: Mao Jinlong <[email protected]>
> Signed-off-by: Sai Prakash Ranjan <[email protected]>

Reviewed-by: Suzuki K Poulose <[email protected]>

> ---
> 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
>

2020-11-23 18:13:51

by Mathieu Poirier

Subject: Re: [PATCH] coresight: tmc-etr: Check if page is valid before dma_map_page()

On Mon, Nov 23, 2020 at 10:46:56AM +0000, Suzuki K Poulose wrote:
> On 11/23/20 10:21 AM, Sai Prakash Ranjan wrote:
> > From: Mao Jinlong <[email protected]>
> >
> > 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: [email protected]
> > Signed-off-by: Mao Jinlong <[email protected]>
> > Signed-off-by: Sai Prakash Ranjan <[email protected]>
>
> Reviewed-by: Suzuki K Poulose <[email protected]>
>

Applied - thanks

Mathieu

> > ---
> > 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
> >
>