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b=L+lRb7tgu/5dsyOmtNeQsYQUgYNKPqVooCkrHEGDMjkgJ0nIp1gZ53JowXggaCgK9 jbspgOy7SIiuWTL/0cUBRj1CMIeDHzxtEh7Z/QV+swxfnuxuv3SLoHennW0zErr4jG P/U6x1Xu/oa4dK1kzkdhB9nySFbgXzUbjqYsqbn0= Date: Mon, 19 Oct 2026 10:58:44 -0700 From: Andrew Morton To: Yosry Ahmed Cc: Nikola Ciprich , Sean Christopherson , Borislav Petkov , David Laight , Rik van Riel , ljs@kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, david@kernel.org, Mike Rapoport , Dave Hansen , Pedro Falcato , Kiryl Shutsemau , luizcap@redhat.com, pbonzini@redhat.com, Tal Zussman , Matt Fleming , gregkh@linuxfoundation.org, sashal@kernel.org Subject: Re: hunting memory corruption bug in 6.18.x Message-Id: <20261019105844.02d4623b7063fec25ebd34ad@linux-foundation.org> In-Reply-To: References: <20261014235736.GCatAW8GD0GlYumL4l@fat_crate.local> <20261015172820.7961d2c0def74d41cc6c4b0c@linux-foundation.org> <20261016031242.GDatGWKo98YSOhEOOn@fat_crate.local> <20261015211832.45d87fab15bb3e0bbc2f47cb@linux-foundation.org> <20261016054954.GEatG7AgMNFRkiTo1H@fat_crate.local> <20261018201538.d0957878f378a9821852836f@linux-foundation.org> <20261019083529.a81910ac0976c1a5687d4c6a@linux-foundation.org> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) X-Archived-By: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: A46F380006 X-Stat-Signature: 1s8jhxdtg4sjd8iqhfhonuxptx9prpq8 X-Spam-Status: No, score=-12.4 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_PASS, SPF_PASS autolearn=ham autolearn_force=no version=4.0.1 X-Rspam-User: X-HE-Tag: 1792432726-189465 X-HE-Meta: U2FsdGVkX1/1Yji4+yJcMYL6wR997DegCdIufg7Z12YtOis1CxdRtKJ/yE8wF3u3ftZ20XmZsLttlBaOPfUA0oSylRwFE/bnedynSuxwURHTKlAPXwVPLhZa1ke4H1r0VMqpIx+H4IDev8d+DiEJbZIThwPM4SFHuzLUV8kPTlFCQqnSvMv0wvld6wP2F0ajHbDvCFywl0bw5+v1ULQwBPwMXiGjrCrBX6fOpsBT1zBVaQJO/ta0KhJ7Z0pR4w3xcSPL+FijdI6nBfjwYBhTlRYQothfb8fGh3HREfIVIcUqavymcOIUCxmg6U29OTBEfO/CA3iufDtMDjgFwWXjQSVMM+ZJhZIfvl/WW/Z9MXhpwyRG+WiZp0LMs5BfGwPGa7j+LXk/u8y9ri94KvxIlBZWHb8EmWSSyguB4hvxoS+GCihmFzlx2vkT6RsO5k/9OcHRJQ8H6KORzWk65nkwBiwm+Cf4T7t2VUyUSGMlJ+ozvtm1HcJ80BbQO4KipMh69l79ZtOQyHWPC1pWVaV1xxG1dS6J2ObfhIO+FGgJ9csaPVryfN4GYJe+kyb5t3Iw3BkZCLWL6Ot6x9t8WPyDRCkNV9TKivDgTylsstfhTPmA3FQIOHn9xV957/QA/K/QBs71vDVMX6JQ6FcuepMBbknqh2izkU3cubqU+pt1RR7ixyeAKOkv/kvl79aQp6TJbtQbZKsE5BODxVbokMdD1hecg1+an0hANt7tA8C4F7Rd/n7hJm8KBbxqM8wsfPfJaTDMXdb6NSM83ZKgvHCOJN/qNYqAgJcs68FXBtVRv5uXf1RnNcgVoiHdEK4Af73WClqA0oKiju061Yu92L/gMPaVknD/SDcp6CTlqFum+akw2lVOUSb+GdeHtczbdzKSoOWbjiw38llqCA/3ZdXLbQ99VXTD+hEvY/EUpM4OsXpSWXNEMOzpVS/4gdP0GHpixPNgSY7Aq4iDI0DGMIN N9ZQKq2L ReL7hPZF+zuXDR0HJWpnLtgYuVV00cUw0d2VtwIxHe0w9sU1tZx8fvkSgBppZazAUna3IWMy4dU4zn+c5Kt8EBs1Er+alDd549uH49Y/pubrEbNzhWy8Gbq9KGXSjp7xWU69ArcJHX5ZXbYUiFfDNsu6w95baD2CYvMINIZUi5t/TqDvo9SxBd1RjWebHs5sZ+2VewAH1XDSKxeu9lg/cN9wAEUxQwRAL7ZYvxB3hF0A5qwNXCzIfkPPVjZu78vQ4saZYJ/CCxVwfhsqRgjoU3wnvinEJBfA0IKxG3qlDc4XQHspsul19Sxu8HSXOvltqbuPsNYP3Hbqun5CtSbAwZD2Sh2pCaHTWkJaA 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 On Mon, 19 Oct 2026 10:39:30 -0700 Yosry Ahmed wrote: > I am glad the commit fixed your problem! > > > > > Great, thanks. > > > > oops, we haven't been cc'ing Yosry. > > > > > Definitely a -stable candidate. Andrew, will you send it to Greg, or shall I? > > > > I volunteer Yosry or Sean ;) > > > > I think 55780d8a1dcc should be repackaged before sending over to the > > -stable people. Its changelog is very wrong: "The bug is benign > > though". Update the changelog to explain that the bug is in fact evil. > > Otherwise -stable and further downstream won't understand why we sent > > it to them and won't understand the impact. > > It was found through code inspection, there weren't any symptoms, and > I think I know why my analysis was incomplete. It assumes that > svm_recalc_instruction_intercepts() already ran at least once for L1 > (vmcb01) to configure its intercepts, which generally must be the case > (L1 must start L2), except during migration :') > > About repackaging, yeah we can add a note about the new finding and > the necessity of the backport. One question tho, is there a way to > send a patch to "all" stable branch (the same effect as adding Cc: > stable retroactively), or do I need to send separate backports to all > open stable branches? As far as I understand, a cc:stable and a Fixes: will result in it being backported into every tree which has the Fixes: target commit. > > > > And that repackaging would be an opportunity to add > > Reported-by:/Closes:/Tested-by: you, which is the least we can do to > > thank you for all this diligent work! > > Will do. Thanks.