lkml.org 
[lkml]   [2018]   [Nov]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] drm/omap: dss: do not allow devm_kasprintf() to fail
Date
omapdss_display_init() is called by multiple drivers and does not expect
a return value so without changing all call-sites the low-probability
failure of devm_kasprintf() can not be reported up the call stack. As
the amount allocated here is very small (<= 16 bytes) and it is an
initialization function that most likely will be called during system
initialization it should be OK to use __GFP_NOFAIL here to prevent
devm_kasprintf() from returning NULL.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Fixes: 36c61ae2b755 ("drm/omap: dss: Remove display ordering from dss/display.c")
---

Problem located with experimental coccinelle script

While the use of __GFP_NOFAIL is to be limited (small infrequent
allocations) this case does seems suitable as it is rare and small
(initialization) .As all the current drivers using
omapdss_display_init() currently seem not to initialize dssdev->name
prior to calling omapdss_display_init() and the unlikely failure
case can not be reasonably responded (returns void) not allowing
a allocation failure here should be acceptable.

Patch was compile tested with: omap2plus_defconfig (implies OMAP_DSS_BASE=m)

Patch is against 4.20-rc3 (localversion-next is next-20181123)

drivers/gpu/drm/omapdrm/dss/display.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/omapdrm/dss/display.c b/drivers/gpu/drm/omapdrm/dss/display.c
index 34b2a4e..7dbe874 100644
--- a/drivers/gpu/drm/omapdrm/dss/display.c
+++ b/drivers/gpu/drm/omapdrm/dss/display.c
@@ -45,7 +45,8 @@ void omapdss_display_init(struct omap_dss_device *dssdev)
of_property_read_string(dssdev->dev->of_node, "label", &dssdev->name);

if (dssdev->name == NULL)
- dssdev->name = devm_kasprintf(dssdev->dev, GFP_KERNEL,
+ dssdev->name = devm_kasprintf(dssdev->dev,
+ GFP_KERNEL | __GFP_NOFAIL,
"display%u", id);
}
EXPORT_SYMBOL_GPL(omapdss_display_init);
--
2.1.4
\
 
 \ /
  Last update: 2018-11-23 13:09    [W:0.024 / U:0.580 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site