Re: [PATCH] mm/slub: Add slub_debug option to panic on memory corruption

Christoph Lameter
2021-03-09T14:56:35Z

On Tue, 9 Mar 2021, Georgi Djakov wrote:

> Being able to stop the system immediately when a memory corruption
> is detected is crucial to finding the source of it. This is very
> useful when the memory can be inspected with kdump or other tools.

Hmmm.... ok.

> static void restore_bytes(struct kmem_cache *s, char *message, u8 data,
> void *from, void *to)
> {
> + if (slub_debug & SLAB_CORRUPTION_PANIC)
> + panic("slab: object overwritten\n");
> slab_fix(s, "Restoring 0x%p-0x%p=0x%x\n", from, to - 1, data);
> memset(from, data, to - from);
> }

Why panic here? This should only be called late in the bug reporting when
an error has already been printed.