Re: [PATCH v3 1/2] kunit: add a KUnit test for SLUB debugging functionality

[Vlastimil Babka <vbabka@suse.cz>]

On 3/31/21 10:51 AM, glittao@gmail.com wrote:
> From: Oliver Glitta <glittao@gmail.com>
> 
> SLUB has resiliency_test() function which is hidden behind #ifdef
> SLUB_RESILIENCY_TEST that is not part of Kconfig, so nobody
> runs it. KUnit should be a proper replacement for it.
> 
> Try changing byte in redzone after allocation and changing
> pointer to next free node, first byte, 50th byte and redzone
> byte. Check if validation finds errors.
> 
> There are several differences from the original resiliency test:
> Tests create own caches with known state instead of corrupting
> shared kmalloc caches.
> 
> The corruption of freepointer uses correct offset, the original
> resiliency test got broken with freepointer changes.
> 
> Scratch changing random byte test, because it does not have
> meaning in this form where we need deterministic results.
> 
> Add new option CONFIG_SLUB_KUNIT_TEST in Kconfig.
> 
> Add a counter field "errors" to struct kmem_cache to count number
> of errors detected in cache.
> 
> Silence bug report in SLUB test. Add SLAB_SILENT_ERRORS debug flag.
> Add SLAB_SILENT_ERRORS flag to SLAB_NEVER_MERGE, SLAB_DEBUG_FLAGS,
> SLAB_FLAGS_PERMITTED macros.
> 
> Signed-off-by: Oliver Glitta <glittao@gmail.com>

Acked-by: Vlastimil Babka <vbabka@suse.cz>