linux/drivers/mmc
Sergey Shtylyov 103da0667d mmc: core: block: fix sloppy typing in mmc_blk_ioctl_multi_cmd()
Despite mmc_ioc_multi_cmd::num_of_cmds is a 64-bit field, its maximum
value is limited to MMC_IOC_MAX_CMDS (only 255); using a 64-bit local
variable to hold a copy of that field leads to gcc generating ineffective
loop code: despite the source code using an *int* variable for the loop
counters,  the 32-bit object code uses 64-bit unsigned counters.  Also,
gcc has to drop the most significant word of that 64-bit variable when
calling kcalloc() and assigning to mmc_queue_req::ioc_count anyway.
Using the *unsigned int* variable instead results in a better code.

Found by Linux Verification Center (linuxtesting.org) with the SVACE static
analysis tool.

Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Link: https://lore.kernel.org/r/eea3b0bd-6091-f005-7189-b5b7868abdb6@omp.ru
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2022-04-26 14:05:19 +02:00
..
core mmc: core: block: fix sloppy typing in mmc_blk_ioctl_multi_cmd() 2022-04-26 14:05:19 +02:00
host mmc: renesas_sdhi: R-Car V3M also has no HS400 2022-04-26 14:05:19 +02:00
Kconfig treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
Makefile treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00