On Wed, Jan 18, 2017 at 8:17 AM, Michal Hocko <mhocko@xxxxxxxxxx> wrote: > On Wed 18-01-17 10:39:48, Sergey Senozhatsky wrote: >> Cc Dan >> >> On (01/17/17 12:22), Andrew Morton wrote: >> > > https://bugzilla.kernel.org/show_bug.cgi?id=192571 >> > > >> > > --- Comment #1 from Gluzskiy Alexandr <sss123next@xxxxxxx> --- >> > > [199961.576604] ------------[ cut here ]------------ >> > > [199961.577830] kernel BUG at mm/zswap.c:1108! >> >> zswap didn't manage to decompress the page: >> >> static int zswap_frontswap_load(unsigned type, pgoff_t offset, >> struct page *page) >> { >> ... >> dst = kmap_atomic(page); >> tfm = *get_cpu_ptr(entry->pool->tfm); >> ret = crypto_comp_decompress(tfm, src, entry->length, dst, &dlen); >> put_cpu_ptr(entry->pool->tfm); >> kunmap_atomic(dst); >> zpool_unmap_handle(entry->pool->zpool, entry->handle); >> BUG_ON(ret); >> ^^^^^^^^^^^ > > Ugh, why do we even do that? This is not the way how to handle error > situations. AFAIU propagating the error out wouldn't be a big deal > because we would just fallback to regular swap, right? yeah this function definitely should never bug; it's just a callback from the zpool to try to write a page back to the swapcache so the zpool can free a page. It's definitely ok for it to return an error. > -- > Michal Hocko > SUSE Labs > > -- > To unsubscribe, send a message with 'unsubscribe linux-mm' in > the body to majordomo@xxxxxxxxx. For more info on Linux MM, > see: http://www.linux-mm.org/ . > Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a> > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>