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Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , "Matthew Wilcox (Oracle)" , Wei Yang , Yang Shi , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, stable@vger.kernel.org References: <20251023030521.473097-1-ziy@nvidia.com> Content-Language: en-US From: Pankaj Raghav In-Reply-To: <20251023030521.473097-1-ziy@nvidia.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Stat-Signature: w4wyyby5cozji3uf5o46nnxfhqb3z5bg X-Rspamd-Queue-Id: 2663840004 X-Rspamd-Server: rspam06 X-Rspam-User: X-HE-Tag: 1761217831-656659 X-HE-Meta: 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 dKTJzHHw SvTq0Whg5BRbrmi2RYqW6f4V9t9R4Fekou/54TbXujUr7+1e/HsdeqfuHUFacqikFsI5IQc+gB1cuFGsxDQpyPazLisTV8bqWSWKuPjd2+QES76Z3JQ+Lbv6GzH8SayxnHUhHjUBjGhOXeGmbVc32U0qSfhEM63an7LvwbTUTc01D5Y9jP11EbI2D5Zwuk7OJEDj1axsueGWhvT+WDX/2XlZz9QyCXYaJYXcSQGXUFp1KE2RRwEn3/v9KMwaE4bhtPVPA/6Tkeg3yjCYnYdQCUov7UBpPZYS+5sIEgP7copRt0hguTklokWovTdBv2saXc2GNz7SdtA6W9USnXwHPRRQ/ot5LNcwwRQzTKKdAfbx6jR5UEvmuV1aTL4o4lWdM9p0izGnup6NT201Z6bal1YNDOeFFSaqJ92tzHA5AxcDjS9s= 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: List-Subscribe: List-Unsubscribe: On 10/23/25 05:05, Zi Yan wrote: > folio split clears PG_has_hwpoisoned, but the flag should be preserved in > after-split folios containing pages with PG_hwpoisoned flag if the folio is > split to >0 order folios. Scan all pages in a to-be-split folio to > determine which after-split folios need the flag. > > An alternatives is to change PG_has_hwpoisoned to PG_maybe_hwpoisoned to > avoid the scan and set it on all after-split folios, but resulting false > positive has undesirable negative impact. To remove false positive, caller > of folio_test_has_hwpoisoned() and folio_contain_hwpoisoned_page() needs to > do the scan. That might be causing a hassle for current and future callers > and more costly than doing the scan in the split code. More details are > discussed in [1]. > > This issue can be exposed via: > 1. splitting a has_hwpoisoned folio to >0 order from debugfs interface; Is it easy to add a selftest in split_huge_page_test for this scenario? > 2. truncating part of a has_hwpoisoned folio in > truncate_inode_partial_folio(). > -- Pankaj