From: Guenter Roeck <linux@xxxxxxxxxxxx> Subject: checkpatch: do not complain about positive return values starting with EPOLL checkpatch complains about positive return values of poll functions. Example: WARNING: return of an errno should typically be negative (ie: return -EPOLLIN) + return EPOLLIN; Poll functions return positive values. The defines for the return values of poll functions all start with EPOLL, resulting in a number of false positives. An often used workaround is to assign poll function return values to variables and returning that variable, but that is a less than perfect solution. There is no error definition which starts with EPOLL, so it is safe to omit the warning for return values starting with EPOLL. Link: https://lkml.kernel.org/r/20210622004334.638680-1-linux@xxxxxxxxxxxx Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx> Acked-by: Joe Perches <joe@xxxxxxxxxxx> Cc: Ricardo Ribalda <ribalda@xxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- scripts/checkpatch.pl | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/scripts/checkpatch.pl~checkpatch-do-not-complain-about-positive-return-values-starting-with-epoll +++ a/scripts/checkpatch.pl @@ -5462,7 +5462,7 @@ sub process { # Return of what appears to be an errno should normally be negative if ($sline =~ /\breturn(?:\s*\(+\s*|\s+)(E[A-Z]+)(?:\s*\)+\s*|\s*)[;:,]/) { my $name = $1; - if ($name ne 'EOF' && $name ne 'ERROR') { + if ($name ne 'EOF' && $name ne 'ERROR' && $name !~ /^EPOLL/) { WARN("USE_NEGATIVE_ERRNO", "return of an errno should typically be negative (ie: return -$1)\n" . $herecurr); } _