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[209.85.208.44]) by smtp.gmail.com with ESMTPSA id 4fb4d7f45d1cf-64751062081sm10555375a12.34.2025.11.30.14.16.30 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sun, 30 Nov 2025 14:16:30 -0800 (PST) Received: by mail-ed1-f44.google.com with SMTP id 4fb4d7f45d1cf-64165cd689eso6805554a12.0 for ; Sun, 30 Nov 2025 14:16:30 -0800 (PST) X-Forwarded-Encrypted: i=1; AJvYcCWqU72R2H8US6O0s4KYbHq5iSzO8B4D7P186WuMLxR+kG7vvbiyhHd0lpr/5hedoXTGKL3T3DDB8g==@kvack.org X-Received: by 2002:a05:6402:42c7:b0:640:b07c:5704 with SMTP id 4fb4d7f45d1cf-645550f2186mr35236789a12.15.1764540989792; Sun, 30 Nov 2025 14:16:29 -0800 (PST) MIME-Version: 1.0 References: <20251126090505.3057219-1-wozizhi@huaweicloud.com> <20251126185545.GC3538@ZenIV> <20251129033728.GH3538@ZenIV> <20251130030146.GN3538@ZenIV> In-Reply-To: <20251130030146.GN3538@ZenIV> From: Linus Torvalds Date: Sun, 30 Nov 2025 14:16:13 -0800 X-Gmail-Original-Message-ID: X-Gm-Features: AWmQ_bmTUCdJWcv7cINUl1_LNv_Km0lC6yoktUJAc05I0M6Vkfdd5_maAqPfL2E Message-ID: Subject: Re: [RFC][alpha] saner vmalloc handling (was Re: [Bug report] hash_name() may cross page boundary and trigger sleep in RCU context) To: Al Viro Cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-alpha@vger.kernel.org Content-Type: text/plain; charset="UTF-8" X-Stat-Signature: dcupb3qhomhde7oni9droq7e1jqtxw9f X-Rspam-User: X-Rspamd-Queue-Id: 7D23980005 X-Rspamd-Server: rspam09 X-HE-Tag: 1764540993-703392 X-HE-Meta: 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 qQ/t51as 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 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 Sat, 29 Nov 2025 at 19:01, Al Viro wrote: > > + Default is 8Gb total and under normal circumstances, this is so > + far and above what is needed as to be laughable. However, there are > + certain applications (such as benchmark-grade in-kernel web serving) > + that can make use of as much vmalloc space as is available. I wonder if we even need the config variable? Because this reads like the whole feature exists due to the old 'tux' web server thing (from the early 2000's - long long gone, never merged upstream). So I'm not sure there are any actual real use-cases for tons of vmalloc space on alpha. Anyway, I see no real objections to the patch, only a "maybe it could be cut down even more". Linus