Messages in this thread | | | Date | Fri, 14 Oct 2016 01:34:29 +0100 | From | Mark Rutland <> | Subject | Re: [PATCH v2] perf: xgene: Remove bogus IS_ERR() check |
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On Thu, Oct 13, 2016 at 07:18:37PM +0100, Al Viro wrote: > On Thu, Oct 13, 2016 at 11:09:16AM -0700, Tai Nguyen wrote: > > In acpi_get_pmu_hw_inf we pass the address of a local variable to IS_ERR(), > > which doesn't make sense, as the pointer must be a real, valid pointer. > > This doesn't cause a functional problem, as IS_ERR() will evaluate as > > false, but the check is bogus and causes static checkers to complain. > > ... unless the test is actually a misspelled IS_ERR(res) and the current > code is broken by effectively skipping it.
Sure.
In this case, res is a struct resource, so IS_ERR(res) is also bogus.
None of the pointer fields in struct resource are ever set to an ERR_PTR value, so nothing in res is worth checking. Nothing else in the function prior to this would be an ERR_PTR value either.
I believe this case was copy-paste and a thinko. There's some other error handling in the file that does validly have to handle an ERR_PTR value.
Thanks, Mark.
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