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See http://www.infradead.org/rpr.html X-Stat-Signature: smm6o67ug99jug3s4hp67n8c13c46cxs X-Rspam-User: X-Rspamd-Queue-Id: 8890E80025 X-Rspamd-Server: rspam06 X-HE-Tag: 1680620833-337083 X-HE-Meta: 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 9Q16qMrB IpOsZboxMrLTV8x2/vDN4DB1fnl7WUUX4jnlAJfBXD59MycylFBi3QtmsY/0YvX3jEmSfR1VVM0AZexB/XYSSLaigobbIcyonQ5FnX5O4KSP+2qnnN90s/TYcgVF1haCbF6A+a4k552FVYF5Cgd35mwf1MRkvXPllvkjDiK5HzD7MOKN4tR3HMcftBoEH3qAam/JXtHArD+pI1jPJIpiJEKHmLsrVALNSeYf1MdtMHDIUB3lnXSmFqztA8EkB0eHF9id1GqrMav470W8heESKW0iAQo+Ygt2g4jAn69x3zLnTWpq3TEvyvkrWHcDoE3b9OjZ052BPcVpbes5yjeHHXPLnAhgTmSSr9ljA7qUam7a5yax8zvM/+DZp0K5BdclLYqnD9x5xev2LstB4zQNc7TH/9nxzXFbtv5GwjOUuBWF6OY+xdjeDEBo9JAlzst87wdGTZ/5zqzpB4gA= 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 Mon, Apr 03, 2023 at 03:22:17PM +0200, Pankaj Raghav wrote: > zram_bvec_read() is called with the bio set to NULL only in > writeback_store() function. When a writeback is triggered, > zram_bvec_read() is called only if ZRAM_WB flag is not set. That will > result only calling zram_read_from_zspool() in __zram_bvec_read(). > > rw_page callback used to call read_from_bdev_async with a NULL parent > bio but that has been removed since commit 3222d8c2a7f8 > ("block: remove ->rw_page"). > > We can now safely always call bio_chain() as read_from_bdev_async() will > be called with a parent bio set. A WARN_ON_ONCE is added if this function > is called with parent set to NULL. I'm pretty sure this is wrong. I've now sent a series to untangle and fix up the zram I/O path, which should address the underlying issue here. It will obviously conflict with this patch, so maybe the best thing is to get the other page_endio removals into their respective maintainer trees, and then just do the final removal of the unused function after -rc1.