| Message ID | 20220412020834.7161-1-linmq006@gmail.com |
|---|---|
| State | Changes Requested |
| Headers | show |
| Series | mtd: rawnand: Fix return value check of wait_for_completion_timeout | expand |
Hi Miaoqian,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on mtd/nand/next]
[also build test WARNING on linus/master linux/master v5.18-rc2 next-20220411]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/intel-lab-lkp/linux/commits/Miaoqian-Lin/mtd-rawnand-Fix-return-value-check-of-wait_for_completion_timeout/20220412-101006
base: https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git nand/next
config: hexagon-randconfig-r045-20220411 (https://download.01.org/0day-ci/archive/20220412/202204121253.NcZifMQi-lkp@intel.com/config)
compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project fe2478d44e4f7f191c43fef629ac7a23d0251e72)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/3de25b46a3f73a3e0031e5186eb4e2afa9098b46
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Miaoqian-Lin/mtd-rawnand-Fix-return-value-check-of-wait_for_completion_timeout/20220412-101006
git checkout 3de25b46a3f73a3e0031e5186eb4e2afa9098b46
# save the config file to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=hexagon SHELL=/bin/bash drivers/mtd/nand/raw/
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All warnings (new ones prefixed by >>):
>> drivers/mtd/nand/raw/sh_flctl.c:433:6: warning: variable 'ret' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
if (time_left == 0) {
^~~~~~~~~~~~~~
drivers/mtd/nand/raw/sh_flctl.c:447:9: note: uninitialized use occurs here
return ret;
^~~
drivers/mtd/nand/raw/sh_flctl.c:433:2: note: remove the 'if' if its condition is always true
if (time_left == 0) {
^~~~~~~~~~~~~~~~~~~~
drivers/mtd/nand/raw/sh_flctl.c:387:9: note: initialize the variable 'ret' to silence this warning
int ret;
^
= 0
1 warning generated.
vim +433 drivers/mtd/nand/raw/sh_flctl.c
377
378 static int flctl_dma_fifo0_transfer(struct sh_flctl *flctl, unsigned long *buf,
379 int len, enum dma_data_direction dir)
380 {
381 struct dma_async_tx_descriptor *desc = NULL;
382 struct dma_chan *chan;
383 enum dma_transfer_direction tr_dir;
384 dma_addr_t dma_addr;
385 dma_cookie_t cookie;
386 uint32_t reg;
387 int ret;
388 unsigned long time_left;
389
390 if (dir == DMA_FROM_DEVICE) {
391 chan = flctl->chan_fifo0_rx;
392 tr_dir = DMA_DEV_TO_MEM;
393 } else {
394 chan = flctl->chan_fifo0_tx;
395 tr_dir = DMA_MEM_TO_DEV;
396 }
397
398 dma_addr = dma_map_single(chan->device->dev, buf, len, dir);
399
400 if (!dma_mapping_error(chan->device->dev, dma_addr))
401 desc = dmaengine_prep_slave_single(chan, dma_addr, len,
402 tr_dir, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
403
404 if (desc) {
405 reg = readl(FLINTDMACR(flctl));
406 reg |= DREQ0EN;
407 writel(reg, FLINTDMACR(flctl));
408
409 desc->callback = flctl_dma_complete;
410 desc->callback_param = flctl;
411 cookie = dmaengine_submit(desc);
412 if (dma_submit_error(cookie)) {
413 ret = dma_submit_error(cookie);
414 dev_warn(&flctl->pdev->dev,
415 "DMA submit failed, falling back to PIO\n");
416 goto out;
417 }
418
419 dma_async_issue_pending(chan);
420 } else {
421 /* DMA failed, fall back to PIO */
422 flctl_release_dma(flctl);
423 dev_warn(&flctl->pdev->dev,
424 "DMA failed, falling back to PIO\n");
425 ret = -EIO;
426 goto out;
427 }
428
429 time_left =
430 wait_for_completion_timeout(&flctl->dma_complete,
431 msecs_to_jiffies(3000));
432
> 433 if (time_left == 0) {
434 dmaengine_terminate_all(chan);
435 dev_err(&flctl->pdev->dev, "wait_for_completion_timeout\n");
436 ret = -ETIMEDOUT;
437 }
438
439 out:
440 reg = readl(FLINTDMACR(flctl));
441 reg &= ~DREQ0EN;
442 writel(reg, FLINTDMACR(flctl));
443
444 dma_unmap_single(chan->device->dev, dma_addr, len, dir);
445
446 /* ret > 0 is success */
447 return ret;
448 }
449
diff --git a/drivers/mtd/nand/raw/sh_flctl.c b/drivers/mtd/nand/raw/sh_flctl.c index b85b9c6fcc42..4f326a2dd170 100644 --- a/drivers/mtd/nand/raw/sh_flctl.c +++ b/drivers/mtd/nand/raw/sh_flctl.c @@ -385,6 +385,7 @@ static int flctl_dma_fifo0_transfer(struct sh_flctl *flctl, unsigned long *buf, dma_cookie_t cookie; uint32_t reg; int ret; + unsigned long time_left; if (dir == DMA_FROM_DEVICE) { chan = flctl->chan_fifo0_rx; @@ -425,13 +426,14 @@ static int flctl_dma_fifo0_transfer(struct sh_flctl *flctl, unsigned long *buf, goto out; } - ret = + time_left = wait_for_completion_timeout(&flctl->dma_complete, msecs_to_jiffies(3000)); - if (ret <= 0) { + if (time_left == 0) { dmaengine_terminate_all(chan); dev_err(&flctl->pdev->dev, "wait_for_completion_timeout\n"); + ret = -ETIMEDOUT; } out:
wait_for_completion_timeout() returns unsigned long not int. It returns 0 if timed out, and positive if completed. The check for <= 0 is ambiguous and should be == 0 here indicating timeout which is the only error case. Fixes: 83738d87e3a0 ("mtd: sh_flctl: Add DMA capabilty") Signed-off-by: Miaoqian Lin <linmq006@gmail.com> --- drivers/mtd/nand/raw/sh_flctl.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)