Re: [PATCH] x86/numa: Use cpumask_available instead of hardcoded NULL check
From: Ingo Molnar
Date: Tue Aug 02 2022 - 07:07:53 EST
* Siddh Raman Pant <code@xxxxxxxx> wrote:
> GCC warning log:
> ===========================================================================
>
> arch/x86/mm/numa.c: In function ‘cpumask_of_node’:
> arch/x86/mm/numa.c:916:39: warning: the comparison will always evaluate as ‘false’ for the address of ‘node_to_cpumask_map’ will never be NULL [-Waddress]
> 916 | if (node_to_cpumask_map[node] == NULL) {
> | ^~
Your fix makes sense I suppose, but I'm wondering how testing didn't
trigger this warning.
Off-stack isn't a rare config option:
kepler:~/tip> make allmodconfig
#
# No change to .config
#
kepler:~/tip> grep CPUMASK_OFFSTACK .config
CONFIG_CPUMASK_OFFSTACK=y
kepler:~/tip>
What am I missing?
> Fixes: c032ef60d1aa ("cpumask: convert node_to_cpumask_map[] to cpumask_var_t")
> Fixes: de2d9445f162 ("x86: Unify node_to_cpumask_map handling between 32 and 64bit")
These are ancient commits from 2009 & 2011.
Thanks,
Ingo