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t=1777045378; bh=VmyuuW4BreNkPPOMqrGtbTE5hoLsOBMQFeVplDAHz24=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=s6ryWYr7VoiHmsU/LPEaQ8sOkbImRYH85BnfbLA/D//UNSCaO1+d1Z11op+4YpRTc DjYiOy9e7HxQLvmyF1CEtEu8QTzBqrr+Z9uWzluXiEk0VUw0Rj+kYHhxGE1qS/44vQ A/WthNXRAOeTJwN6eqWE+ZnAb9HW8giJB2DBYn5NmrLCPU1nR0Rmysrq9cTekCwTMx WjWZv6QkQ+9OJOvZayC34Boy6gEsTxdVa+P6vRS/+us0IWy+XoQ/Jg2JXZskdaFZlB sznsHHpLQkVlL/K1Xf6e2zDUkp1hLBdzHl2uf474/EYictMBHJFoAn5RDQIXC0Kuk/ epU9q2XEJSzPA== Message-ID: Date: Fri, 24 Apr 2026 17:42:53 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC 0/7] mm: dual-bitmap page allocator consistency checker Content-Language: en-US To: Sasha Levin , akpm@linux-foundation.org, david@kernel.org, corbet@lwn.net Cc: ljs@kernel.org, Liam.Howlett@oracle.com, rppt@kernel.org, surenb@google.com, mhocko@suse.com, skhan@linuxfoundation.org, jackmanb@google.com, hannes@cmpxchg.org, ziy@nvidia.com, linux-mm@kvack.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org References: <20260424140056.2094777-1-sashal@kernel.org> From: "Vlastimil Babka (SUSE)" In-Reply-To: <20260424140056.2094777-1-sashal@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: CD3E380003 X-Stat-Signature: rcxf5xo8cxypusx9idgsimck8c1dd8so X-Rspam-User: X-Rspamd-Server: rspam09 X-HE-Tag: 1777045379-490153 X-HE-Meta: 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 l2TuThEC QeWW18pBtA+c+NTLFvMLmyLZ6xgM2RJQwwEVqUozUWeQLzFnxZS3YJeaxnJpCxSN1byT/u3c/8hW0NqAnwLo6tmgKDaX9rO1e5C4WrwN5y+vAfFAsdfVCgWYOQN4V8pKMbyYlICNsT6zosxkKqV70RYUpG/OIZZi81LYxmNAPhFprM6CPZ7R7mJOajb3onUJJ25+Fs7fSVxHRPOlAJdvw5cGuRK4hekcLq397it0vQpRdVHkZ39qqNgZ+sHhiwMkoRjyh3xA2EZoV5oKMvZXQFQbZwrcRUoiLdB7l Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 4/24/26 16:00, Sasha Levin wrote: > Existing memory debugging tools - KASAN, KFENCE, page_poisoning - detect > access violations and content corruption, but none of them can detect > silent corruption in the page allocator's own metadata. If a hardware > bit flip corrupts an allocation bitmap, the allocator hands out a page An allocation what? The page allocator is a buddy allocator, it has no bitmap to track free/allocated state of pages?