On 14/10/24 14:44, Avri Altman wrote:
While reviewing the SDUC series, Adrian made a comment concerning the memory allocation code in mmc_sd_num_wr_blocks() - see [1]. Prevent memory allocations from triggering I/O operations while ACMD22 is in progress.
[1] https://www.spinics.net/lists/linux-mmc/msg82199.html
Suggested-by: Adrian Hunter adrian.hunter@intel.com Signed-off-by: Avri Altman avri.altman@wdc.com Cc: stable@vger.kernel.org
drivers/mmc/core/block.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c index 04f3165cf9ae..042b0147d47e 100644 --- a/drivers/mmc/core/block.c +++ b/drivers/mmc/core/block.c @@ -995,6 +995,8 @@ static int mmc_sd_num_wr_blocks(struct mmc_card *card, u32 *written_blocks) u32 result; __be32 *blocks; u8 resp_sz = mmc_card_ult_capacity(card) ? 8 : 4;
- unsigned int noio_flag;
- struct mmc_request mrq = {}; struct mmc_command cmd = {}; struct mmc_data data = {};
@@ -1018,9 +1020,13 @@ static int mmc_sd_num_wr_blocks(struct mmc_card *card, u32 *written_blocks) mrq.cmd = &cmd; mrq.data = &data;
- noio_flag = memalloc_noio_save();
- blocks = kmalloc(resp_sz, GFP_KERNEL);
Could have memalloc_noio_restore() here:
memalloc_noio_restore(noio_flag);
but I feel maybe adding something like:
u64 __aligned(8) tiny_io_buf;
to either struct mmc_card or struct mmc_host is better? Ulf, any thoughts?
- if (!blocks)
- if (!blocks) {
return -ENOMEM;memalloc_noio_restore(noio_flag);
- }
sg_init_one(&sg, blocks, resp_sz); @@ -1041,6 +1047,8 @@ static int mmc_sd_num_wr_blocks(struct mmc_card *card, u32 *written_blocks) } kfree(blocks);
- memalloc_noio_restore(noio_flag);
- if (cmd.error || data.error) return -EIO;