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a=rsa-sha256; c=relaxed/relaxed; d=stgolabs.net; s=dreamhost; t=1770848587; bh=PONYIdbDGRxdo56DTcMpUfL2VeqX9vWTpesN1Ub95bk=; h=Date:From:To:Cc:Subject:Content-Type:Content-Transfer-Encoding; b=QU7y1Ajr1a7JKLxkXZWmXPu5llbF+rk9H33Ux5srLDRFR3jGMgNXO3EazwSlJOO74 rFzzSWY8KbDsbgkCUv/ors6d/cg3U6taTgULmVYzyIJCvN1NDpg6BMRs8KPueHJxfZ IuOXzmXb4dpnKIw8uLnHETQifiWtSKFjg4BufO4boU+UPABj5fXjNZsXAYjgCv8T/s q5gktzcj2f6PNrjlJssrVGxJy6Gd/JM8mHRC/WLkVhWxK3JBxn39Vj9pcGh0Hmg1b5 e1PC/NSuvJz3ANjmx+pCcsT8JKySIzDb2g/hLIcMCgHCJaefuF80oZUPOHyGKrfeNZ XGMPLpCreYB2w== Date: Wed, 11 Feb 2026 14:23:03 -0800 From: Davidlohr Bueso To: Thomas =?utf-8?B?SGVsbHN0csOvwr/CvW0=?= Cc: intel-xe@lists.freedesktop.org, Alistair Popple , Ralph Campbell , Christoph Hellwig , Jason Gunthorpe , Jason Gunthorpe , Leon Romanovsky , Andrew Morton , Matthew Brost , John Hubbard , linux-mm@kvack.org, dri-devel@lists.freedesktop.org, stable@vger.kernel.org Subject: Re: [PATCH v5] mm: Fix a hmm_range_fault() livelock / starvation problem Message-ID: <20260211222303.42qfp6rqxxnpfkr4@offworld> Mail-Followup-To: Thomas =?utf-8?B?SGVsbHN0csOvwr/CvW0=?= , intel-xe@lists.freedesktop.org, Alistair Popple , Ralph Campbell , Christoph Hellwig , Jason Gunthorpe , Jason Gunthorpe , Leon Romanovsky , Andrew Morton , Matthew Brost , John Hubbard , linux-mm@kvack.org, dri-devel@lists.freedesktop.org, stable@vger.kernel.org References: <20260210115653.92413-1-thomas.hellstrom@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Disposition: inline Content-Transfer-Encoding: quoted-printable In-Reply-To: <20260210115653.92413-1-thomas.hellstrom@linux.intel.com> User-Agent: NeoMutt/20220429 X-Stat-Signature: qzhjimxt4fxyhmd1s8hgg9ursrhdy7qs X-Rspam-User: X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 4641A1C0010 X-HE-Tag: 1770848588-189023 X-HE-Meta: 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 JGletWEL mIzsaOnPZsOIdVJJlcrn0Q8Ta8fDi1eJWRi9UDRydlRGBF8WS0bZHku+7OIWoz7R2sVW+bEgLtGbGKTgwQegFonKzn86sceZjL0LZm/Gv25H6YClKGDKwbPlW8RCd1XHoy6OWsyVxLTi0eVJk73KF1m+IBR8E68qxuTr3C8zJCxX32+h/j9wS9n0SiNH6YKvEQOoyEPMv+t2jEW+U5xaxuHrxhh/EXYesvodBtLvVW+5eR2xOOvI1ZrDxUcIJ0JJg3ug5WXOhCl4hvnU+Fhsw7G072HWoeWT6iVbYDj6BIq4V9lLS0xVjcvmpV+Y5/nEu0ASrCaFG5L05dF8wcMmzAhy5mT8shLNYKpNoP7GecZfZ5s8= 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 Tue, 10 Feb 2026, Thomas Hellstr=EF=BF=BDm wrote: >@@ -176,7 +176,7 @@ static int migrate_vma_collect_huge_pmd(pmd_t *pmdp, u= nsigned long start, > } > > if (softleaf_is_migration(entry)) { >- migration_entry_wait_on_locked(entry, ptl); >+ softleaf_entry_wait_on_locked(entry, ptl); > spin_unlock(ptl); softleaf_entry_wait_on_locked() unconditionally drops the ptl. > return -EAGAIN; > }