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See http://www.infradead.org/rpr.html X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 332D54000F X-Stat-Signature: o9983uxzqujx6wz96nccka6chq5hxumf X-HE-Tag: 1679567753-153135 X-HE-Meta: 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 2wcgpVn2 X2s6LnZKCKY6HzbBc2yON6fvF1pwjLKpjR07/uQfV3AU5qQjrfSclC+nglF7d4EetsGgmur3vY3Rhion9YkfjDODVfSw7vJsVUTx47d6YCYOVxJRfTfqA6TsNyWcem+1HzvgBphqfZf7xZCdtwODPnSF19ToeajPJX624oSt6nI88PNKQkhvvjnnTD9nOi5neqluQ1k8aum6eUWnYPjfmPUHUyfbjlEBf2kltUYquj196jaoKggmyp/L+V4Zgbuuv6mImccW9LMrI3Jf9fyPY7+mKwC0fhtphH0wXiMT+C/TFbBbgLSkcMV2rCThuIzbGccneL5cKhRpEJds8me8xSyHMchL/7G0cMTZaPuBXUvhs9v6vTPy4xqpBvT07FDZlGNdV0QP8Zxixmz6F+5m/igODJohb9C6uz/v4KehC12wA+ugmxHOinUcqA66PdjArLfRiqDFbmTC+4Ig= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Mar 22, 2023 at 02:50:09PM +0100, Pankaj Raghav wrote: > - if (!parent) > - bio->bi_end_io = zram_page_end_io; > - else > + if (parent) I don't think a non-chained bio without and end_io handler can work. This !parent case seems to come from writeback_store, and as far as I can tell is broken already in the current code as it just fires off an async read without ever waiting for it, using an on-stack bio just to make things complicated. The bvec reading code in zram is a mess, but I have an idea how to clean it up with a little series that should also help with this issue.