On Thu, 24 Jan 2019 15:00:23 +0800 <miles.chen@xxxxxxxxxxxx> wrote: > From: Miles Chen <miles.chen@xxxxxxxxxxxx> > > When debugging slab errors in slub.c, sometimes we have to trigger > a panic in order to get the coredump file. Add a debug option > SLAB_WARN_ON_ERROR to toggle WARN_ON() when the option is set. > > Change since v1: > 1. Add a special debug option SLAB_WARN_ON_ERROR and toggle WARN_ON() > if it is set. > 2. SLAB_WARN_ON_ERROR can be set by kernel parameter slub_debug. > Hopefully the slab developers will have an opinion on this. > --- a/Documentation/vm/slub.rst > +++ b/Documentation/vm/slub.rst > @@ -52,6 +52,7 @@ Possible debug options are:: > A Toggle failslab filter mark for the cache > O Switch debugging off for caches that would have > caused higher minimum slab orders > + W Toggle WARN_ON() on slab errors > - Switch all debugging off (useful if the kernel is > configured with CONFIG_SLUB_DEBUG_ON) This documentation is poorly phrased. The term "toggle" means to invert the value of a boolean: if it was 1, make it 0 and if it was 0, make it 1. But that isn't what these options do. Something like "enable/disable" would be better. So... --- a/Documentation/vm/slub.rst~mm-slub-introduce-slab_warn_on_error-fix +++ a/Documentation/vm/slub.rst @@ -49,10 +49,10 @@ Possible debug options are:: P Poisoning (object and padding) U User tracking (free and alloc) T Trace (please only use on single slabs) - A Toggle failslab filter mark for the cache + A Enable/disable failslab filter mark for the cache O Switch debugging off for caches that would have caused higher minimum slab orders - W Toggle WARN_ON() on slab errors + W Enable/disable WARN_ON() on slab errors - Switch all debugging off (useful if the kernel is configured with CONFIG_SLUB_DEBUG_ON) _
