On Friday 04 May 2018 09:59 PM, Lorenzo Pieralisi wrote: > On Tue, Apr 10, 2018 at 09:04:06PM +0800, Jia-Ju Bai wrote: >> pci_epf_test_write() is never called in atomic context. >> >> The call chain ending up at pci_epf_test_write() is: >> [1] pci_epf_test_write() <- pci_epf_test_cmd_handler() >> >> pci_epf_test_cmd_handler() is set as a parameter of INIT_DELAYED_WORK() >> in pci_epf_test_probe(). >> This function is not called in atomic context. >> >> Despite never getting called from atomic context, pci_epf_test_write() >> calls mdelay() to busily wait. >> This is not necessary and can be replaced with usleep_range() to >> avoid busy waiting. >> >> This is found by a static analysis tool named DCNS written by myself. >> And I also manually check it. >> >> Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxxxx> >> --- >> drivers/pci/endpoint/functions/pci-epf-test.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) > > I'd request Kishon's ACK on this. sorry, missed this before. Acked-by: Kishon Vijay Abraham I <kishon@xxxxxx> > > Thanks, > Lorenzo > >> diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c >> index f9308c2..2f0642e 100644 >> --- a/drivers/pci/endpoint/functions/pci-epf-test.c >> +++ b/drivers/pci/endpoint/functions/pci-epf-test.c >> @@ -237,7 +237,7 @@ static int pci_epf_test_write(struct pci_epf_test *epf_test) >> * wait 1ms inorder for the write to complete. Without this delay L3 >> * error in observed in the host system. >> */ >> - mdelay(1); >> + usleep_range(1000, 2000); >> >> kfree(buf); >> >> -- >> 1.9.1 >>
