| Message ID | 685f452cacc74f4983aaff2bc28a02a95e8aa8b7.1681414375.git.christophe.jaillet@wanadoo.fr (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Headers | show |
| Series | video: fbdev: mmp: Fix deferred clk handling in mmphw_probe() | expand |
On Thu, Apr 13, 2023 at 09:33:17PM +0200, Christophe JAILLET wrote: > When dev_err_probe() is called, 'ret' holds the value of the previous > successful devm_request_irq() call. > 'ret' should be assigned with a meaningful value before being used in > dev_err_probe(). > > While at it, use and return "PTR_ERR(ctrl->clk)" instead of a hard-coded > "-ENOENT" so that -EPROBE_DEFER is handled and propagated correctly. > > Fixes: 81b63420564d ("video: fbdev: mmp: Make use of the helper function dev_err_probe()") > Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> > --- Presumably you already wrote a Coccinelle script for this but I've added it to Smatch as well. regards, dan carpenter diff --git a/check_zero_to_err_ptr.c b/check_zero_to_err_ptr.c index 88ca0285948a..fa2a1f1603b2 100644 --- a/check_zero_to_err_ptr.c +++ b/check_zero_to_err_ptr.c @@ -157,11 +157,12 @@ static void match_err_ptr(const char *fn, struct expression *expr, void *data) { struct expression *arg_expr; struct sm_state *sm, *tmp; + int arg = PTR_INT(data); if (is_impossible_path()) return; - arg_expr = get_argument_from_call_expr(expr->args, 0); + arg_expr = get_argument_from_call_expr(expr->args, arg); sm = get_sm_state_expr(SMATCH_EXTRA, arg_expr); if (!sm) return; @@ -194,13 +195,36 @@ static void match_err_ptr(const char *fn, struct expression *expr, void *data) } END_FOR_EACH_PTR(tmp); } +static void match_err_ptr_or_zero(const char *fn, struct expression *expr, void *data) +{ + struct expression *arg; + struct range_list *rl; + char *name; + + if (is_impossible_path()) + return; + + arg = get_argument_from_call_expr(expr->args, 0); + get_absolute_rl(arg, &rl); + + if (rl_intersection(rl, valid_ptr_rl)) + return; + + name = expr_to_str(arg); + sm_warning("'%s' is never a valid pointer", name); + free_string(name); +} + void check_zero_to_err_ptr(int id) { if (option_project != PROJ_KERNEL) return; my_id = id; - add_function_hook("ERR_PTR", &match_err_ptr, NULL); - add_function_hook("ERR_CAST", &match_err_ptr, NULL); - add_function_hook("PTR_ERR", &match_err_ptr, NULL); + add_function_hook("ERR_PTR", &match_err_ptr, INT_PTR(0)); + add_function_hook("ERR_CAST", &match_err_ptr, INT_PTR(0)); + add_function_hook("PTR_ERR", &match_err_ptr, INT_PTR(0)); + add_function_hook("dev_err_probe", &match_err_ptr, INT_PTR(1)); + + add_function_hook("ERR_PTR_OR_ZERO", &match_err_ptr_or_zero, NULL); }
On Sat, Apr 15, 2023 at 04:09:03PM +0300, Dan Carpenter wrote: > On Thu, Apr 13, 2023 at 09:33:17PM +0200, Christophe JAILLET wrote: > > When dev_err_probe() is called, 'ret' holds the value of the previous > > successful devm_request_irq() call. > > 'ret' should be assigned with a meaningful value before being used in > > dev_err_probe(). > > > > While at it, use and return "PTR_ERR(ctrl->clk)" instead of a hard-coded > > "-ENOENT" so that -EPROBE_DEFER is handled and propagated correctly. > > > > Fixes: 81b63420564d ("video: fbdev: mmp: Make use of the helper function dev_err_probe()") > > Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> > > --- > > Presumably you already wrote a Coccinelle script for this but I've added > it to Smatch as well. Here is this warning: drivers/video/fbdev/mmp/hw/mmp_ctrl.c:518 mmphw_probe() warn: passing zero to 'dev_err_probe' Other warnings. All five are interesting. drivers/power/supply/rt9467-charger.c:1026 rt9467_request_interrupt() warn: passing zero to 'dev_err_probe' drivers/pci/controller/dwc/pcie-bt1.c:601 bt1_pcie_add_port() warn: passing zero to 'dev_err_probe' drivers/spi/spi-sprd-adi.c:570 sprd_adi_probe() warn: passing zero to 'dev_err_probe' drivers/soc/qcom/icc-bwmon.c:776 bwmon_probe() warn: passing zero to 'dev_err_probe' drivers/soc/qcom/icc-bwmon.c:781 bwmon_probe() warn: passing zero to 'dev_err_probe' regards, dan carpenter
Le 19/04/2023 à 06:59, Dan Carpenter a écrit : > On Sat, Apr 15, 2023 at 04:09:03PM +0300, Dan Carpenter wrote: >> On Thu, Apr 13, 2023 at 09:33:17PM +0200, Christophe JAILLET wrote: >>> When dev_err_probe() is called, 'ret' holds the value of the previous >>> successful devm_request_irq() call. >>> 'ret' should be assigned with a meaningful value before being used in >>> dev_err_probe(). >>> >>> While at it, use and return "PTR_ERR(ctrl->clk)" instead of a hard-coded >>> "-ENOENT" so that -EPROBE_DEFER is handled and propagated correctly. >>> >>> Fixes: 81b63420564d ("video: fbdev: mmp: Make use of the helper function dev_err_probe()") >>> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> >>> --- >> >> Presumably you already wrote a Coccinelle script for this but I've added >> it to Smatch as well. No I haven't. I've spotted it while looking at some devm_clk_get_optional() candidate with grep. git grep -A5 devm_clk_get | grep -B5 ENOENT Not perfect, but sometimes this kind of approach can find interesting things coccinelle would miss. As an example, the bitmap_alloc patch on sh4 was found this way, with grep. So nice to have it in smatch, ;-) CJ > > Here is this warning: > drivers/video/fbdev/mmp/hw/mmp_ctrl.c:518 mmphw_probe() warn: passing zero to 'dev_err_probe' > > Other warnings. All five are interesting. > drivers/power/supply/rt9467-charger.c:1026 rt9467_request_interrupt() warn: passing zero to 'dev_err_probe' > drivers/pci/controller/dwc/pcie-bt1.c:601 bt1_pcie_add_port() warn: passing zero to 'dev_err_probe' > drivers/spi/spi-sprd-adi.c:570 sprd_adi_probe() warn: passing zero to 'dev_err_probe' > drivers/soc/qcom/icc-bwmon.c:776 bwmon_probe() warn: passing zero to 'dev_err_probe' > drivers/soc/qcom/icc-bwmon.c:781 bwmon_probe() warn: passing zero to 'dev_err_probe' > > regards, > dan carpenter > >
On 4/13/23 21:33, Christophe JAILLET wrote: > When dev_err_probe() is called, 'ret' holds the value of the previous > successful devm_request_irq() call. > 'ret' should be assigned with a meaningful value before being used in > dev_err_probe(). > > While at it, use and return "PTR_ERR(ctrl->clk)" instead of a hard-coded > "-ENOENT" so that -EPROBE_DEFER is handled and propagated correctly. > > Fixes: 81b63420564d ("video: fbdev: mmp: Make use of the helper function dev_err_probe()") > Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> > --- > drivers/video/fbdev/mmp/hw/mmp_ctrl.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) applied. Thanks! Helge > > diff --git a/drivers/video/fbdev/mmp/hw/mmp_ctrl.c b/drivers/video/fbdev/mmp/hw/mmp_ctrl.c > index a9df8ee79810..51fbf02a0343 100644 > --- a/drivers/video/fbdev/mmp/hw/mmp_ctrl.c > +++ b/drivers/video/fbdev/mmp/hw/mmp_ctrl.c > @@ -514,9 +514,9 @@ static int mmphw_probe(struct platform_device *pdev) > /* get clock */ > ctrl->clk = devm_clk_get(ctrl->dev, mi->clk_name); > if (IS_ERR(ctrl->clk)) { > + ret = PTR_ERR(ctrl->clk); > dev_err_probe(ctrl->dev, ret, > "unable to get clk %s\n", mi->clk_name); > - ret = -ENOENT; > goto failed; > } > clk_prepare_enable(ctrl->clk);
diff --git a/drivers/video/fbdev/mmp/hw/mmp_ctrl.c b/drivers/video/fbdev/mmp/hw/mmp_ctrl.c index a9df8ee79810..51fbf02a0343 100644 --- a/drivers/video/fbdev/mmp/hw/mmp_ctrl.c +++ b/drivers/video/fbdev/mmp/hw/mmp_ctrl.c @@ -514,9 +514,9 @@ static int mmphw_probe(struct platform_device *pdev) /* get clock */ ctrl->clk = devm_clk_get(ctrl->dev, mi->clk_name); if (IS_ERR(ctrl->clk)) { + ret = PTR_ERR(ctrl->clk); dev_err_probe(ctrl->dev, ret, "unable to get clk %s\n", mi->clk_name); - ret = -ENOENT; goto failed; } clk_prepare_enable(ctrl->clk);
When dev_err_probe() is called, 'ret' holds the value of the previous successful devm_request_irq() call. 'ret' should be assigned with a meaningful value before being used in dev_err_probe(). While at it, use and return "PTR_ERR(ctrl->clk)" instead of a hard-coded "-ENOENT" so that -EPROBE_DEFER is handled and propagated correctly. Fixes: 81b63420564d ("video: fbdev: mmp: Make use of the helper function dev_err_probe()") Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> --- drivers/video/fbdev/mmp/hw/mmp_ctrl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)