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charset="UTF-8" X-Stat-Signature: do7mb17dujk4nzy7eos7akf7acbihwzt X-Spam-Status: No, score=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_PASS, SPF_PASS,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=4.0.1 X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: A088E1C000C X-Rspam-User: X-HE-Tag: 1792445489-974796 X-HE-Meta: U2FsdGVkX18Gb1hr2PZ8lJ7WswzWSbGHCwzgra7TJLGJdvo7dQJOd0kAsb52yPemCS7eeReU81mwtklkJMuqK9vMeJ8Er1km8H+/zhhb5K4kL0VDLCcKRRXbQLxqyoM01c87+ZIgA3GGqkz/2dg4+m1qC9bl/Imdcbnfuhrz2gkEJ2+RAif2qxHZmrEIt/m05HBcYH0Rwv/7qDfZBGG6WxYFRcDxWFvWyoAXWHDMRmkfgxtTy0K+VliLqy8hSkOgIuKSUty8cq8uORA1CCvxrUIFfcB/YjzH3nsQiCFjk/vj7YsMwC8mNtIg3meJFv/KuLw2AJE0WY7cP/Y30GZnGT1NCvanFlA4U8QkiYe5+kHU23el/UG3RXxczLade0Fe9A8qZkvvu0AvC9RCTuh8QSwX9awSt7xQv0T1OxN8y6vgv+RcrK7eWXoa2m7261h5ZH6MOv3YgyaZJJn5aRO6ZNJ7SI8cQ5LHa4bNEXtZ604eIL/sdcd4f8zp547pQxvEyOzoNMd3sdx1aSZmcPdYWpn5qx2wGx+morn6astCH13AMjuw7Q40lPsLMfbV4vN55nrDrpeLr6epQbjp/NjMTXyCCHAMpr5kguA135syY9iaG6HTl+GsyJcdRDN8lb2YXHD7Y/WeYRtduaptIl/qgZ4Sa4bnFIwELLlaMTlkshueZzdV02DXk6eY186wO3iMMKIx56hjIuOG1wbv2mXNLL1/MYRWD/MVN4A+zHAykuThgZGvF2KVHwx5MV6W09HSNR54bCkINUR1Q5P9YZizLOvqZ/OVZbc2SQ3IENn6YRdxUARljZUrrurvGuOzpgAndxp3UqeEK5O7fXMeXZ4nBgR+6gj+12XtPcXoNABXLZvIvW+YTa6OkyKVanM/C9jUnmm67cPC3fOQQysPr6YMknlAB9WjCNbUJg0JQCQesEuvowbbudcJ8OJcltvvbwC7kbE00FwkxRUAX1PNSSB Uz0pXuZy 3qTZYqKJJv9N2cp1Mh+9uc8BnwhsYuLCdZGvKYlIZCiXg1X1krp6cA9mkvdB6X9gYfEybtkYaQCRmkGDZXcJoOwckBB5i4AxMVsP0DF/ileog5H+VqdAndayGaAhDyTD+H5ZyKov3O6F7ppiQXYTb7w1aj6HcuJE1st+hHXCe7q9DmGhlE5f17+35WvWgQjDekCTWzuGknm4Yaczicq5OO3wH+0oxdsUVu1npd/BB2pt03iD7SDrvvFraBuh0OkLTvGkwh7iqJAxJDyCWONe/lGIwc23gjnuz1QIP3GWJ//XELJTQlFRkUoe/Jef0a+GvJbZrA7P0w9ckr9JDo5CuHN4A7FDMfsibz3brwtIYwVzhjqss/tudaoR3Q65Is5m3VMtXNnfw/UZHDRvIZi6rxsu3MJmKcjTzIu8K0uD2D+PM+60pjgRwreCvxzgqnr2vYXpZbBkhIaFGrxmfOEnKfT4Ru2al0zp5fkOt2h/uKLYgWuNRY2eNRCZ7QdQ4/py+UF1fpAant37DTGEzhO1ECscD9+D57b6ZTGd6qrNicTzNhWK624FIPUEfaFt3EhcCuJpr7pFULPosEEtqFL5FRGVvs1vHlgNlInuT Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 Prevent the windows of bridges preserved across Live Update from being released during the recursive "realloc" failure paths by adding a check for pci_liveupdate_is_incoming() to pci_bridge_release_resources(), and log that the window was not released, similar to the message that pci_release_resource() logs when it releases a window. This prevents the PCI core from forcibly releasing a preserved bridge window to satisfy the resource needs of a failing child device. Instead, the child's resources simply fail to be allocated. This should never happen in practice though, since the previous kernel should have established a sane resource allocation before kexec. Assisted-by: LLM Signed-off-by: David Matlack --- drivers/pci/setup-bus.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index b82440394ee2..7283c4be803e 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -1700,6 +1700,12 @@ static void pci_bridge_release_resources(struct pci_bus *bus, idx = pci_resource_num(dev, b_win); + if (pci_liveupdate_is_incoming(dev)) { + pci_info(dev, "%s %pR: not releasing window of bridge preserved across Live Update\n", + pci_resource_name(dev, idx), b_win); + return; + } + /* If there are children, release them all */ release_child_resources(b_win); -- 2.56.0.212.g129ede20d9-goog