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Miller" , Johannes Weiner , Nhat Pham , Chengming Zhou , Nick Terrell , David Sterba , SJ Park , Chris Li , Giovanni Cabiddu , Suman Kumar Chakraborty , linux-crypto@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" On Thu, Oct 22, 2026 at 12:15:51PM -0700, Yosry Ahmed wrote: > On Thu, Oct 22, 2026 at 11:33 AM Suseendran Bhaskaran > wrote: [...] > > Since dlen is only valid when !comp_ret, we could normalize comp_ret > > first when !comp_ret and then just check 'if (comp_ret)': > > > > diff --git a/mm/zswap.c b/mm/zswap.c > > --- a/mm/zswap.c > > +++ b/mm/zswap.c > > @@ -874,19 +874,24 @@ static bool zswap_compress(struct page *page, struct zswap_entry *entry, > > */ > > comp_ret = crypto_wait_req(crypto_acomp_compress(acomp_ctx->req), &acomp_ctx->wait); > > dlen = acomp_ctx->req->dlen; > > + if (!comp_ret) { > > + if (dlen == PAGE_SIZE) > > + comp_ret = -ENOSPC; > > + else if (WARN_ON_ONCE(!dlen || dlen > PAGE_SIZE)) > > + comp_ret = -EINVAL; > > + } > > > > /* > > * If a page cannot be compressed into a size smaller than PAGE_SIZE, > > * save the content as is without a compression, to keep the LRU order > > * of writebacks. If writeback is disabled, reject the page since it > > * only adds metadata overhead. swap_writeout() will put the page back > > * to the active LRU list in the case. > > */ > > - if (comp_ret || !dlen || dlen >= PAGE_SIZE) { > > + if (comp_ret) { > > rcu_read_lock(); > > if (!mem_cgroup_zswap_writeback_enabled( > > folio_memcg(page_folio(page)))) { > > rcu_read_unlock(); > > - comp_ret = comp_ret ? comp_ret : -EINVAL; > > goto unlock; > > } > > > > Does this look good to you? > > Yes. I assume this is completely independent from patch 1, so we can > tell Herbert to pick up patch 1 and send this separately? Yes, this change is completely independent from patch 1. Herbert can pick up patch 1 as-is. I will address the latest Sashiko finding on patch 2 and send the updated patch as a standalone change separately.