From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A00FC375AC3 for ; Tue, 3 Mar 2026 09:04:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772528696; cv=none; b=uD8Aiv0FlVO4axkOjZ0w27gTIQjpDa+OP5rDbPk7cBuvOifyWetOKfH9QxAwnaj/+/uGqJ6402pDH6KDcv1cShUpOdoLiFgPsY06mJwoXjqwjfPmyUpM4VidGUys7Z8P7bNXZbotWMWp1/nE+uXe17F+qqi4ZmSRfvLMvX+r8BQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772528696; c=relaxed/simple; bh=v4W07b6IBE11k67IglXjM+gXfTvQJy/SRQ49IMklHJI=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=XCuVwOFIzk3lyOkRH3PTJ9lDuPikKpWzZCKk0uWkReZTqT7Y9xuMrvIuJF5zBW58ySEtQSJ5g+e1oKzHMFFMlUDcRS6A6Qc2tfWq7g5FJo7AuaMR6bXCIJNomWpBRQ46+Gf2X14GEZ9uE4pQ6eQFbIAa2XLDBK6UB8pquXxCINg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=DlA3KLhz; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="DlA3KLhz" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 07E9EC2BC87; Tue, 3 Mar 2026 09:04:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772528696; bh=v4W07b6IBE11k67IglXjM+gXfTvQJy/SRQ49IMklHJI=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=DlA3KLhzMnXcvgir/3qFCtKeIstacO9g25eq0MMpnCpjzseYiIdnCDEDoWq6eBChp cAn42ionD+v1beSsyyD61QZkAkXal3OuojL/4Y7ZuCZIfyjZrNmlnlvy0D8Z4zzxRW oGXITl6k7yV7RFycNb49jo2RIIL6tJiXCivp3fA7fyPC5qhwbZesrQtCyzXrMGWys3 HVx919k23NLUcITmDq/V0TOfUWF06nLGSiBlEwx1T1DQYoeNH8kdAFdeBh210HA3iJ FMTVF9G5VVlU7dbXmTVvU6tj+CyfhJDsSrHMp4lpKiPHEQJA+qIaMiOn1KcgzbOW3o ht68qwXEbTKhg== Message-ID: Date: Tue, 3 Mar 2026 10:04:51 +0100 Precedence: bulk X-Mailing-List: ksummit@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC] kallsyms: embed source file:line info in kernel stack traces Content-Language: en-US To: Tomasz Figa , Richard Weinberger Cc: Sasha Levin , Linus Torvalds , Andrew Morton , Geert Uytterhoeven , Konstantin Ryabitsev , ksummit , laurent pinchart , Thorsten Leemhuis , Steven Rostedt , users References: <20260302202828.2722037-1-sashal@kernel.org> <91334269.1714.1772519173246.JavaMail.zimbra@nod.at> From: "Vlastimil Babka (SUSE)" In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 3/3/26 07:48, Tomasz Figa wrote: >> > Memory footprint measured with a simple KVM guest x86_64 config: >> > >> > Table: 4,597,583 entries from 4,841 source files >> > lineinfo_addrs[] 4,597,583 x u32 = 17.5 MiB >> > lineinfo_file_ids[] 4,597,583 x u16 = 8.8 MiB >> > lineinfo_lines[] 4,597,583 x u32 = 17.5 MiB >> > file_offsets + filenames ~ 0.1 MiB >> > Total .rodata increase: ~ 44.0 MiB >> > >> > vmlinux (stripped): 529 MiB -> 573 MiB (+44 MiB / +8.3%) >> >> Hm, that's a significant increase. > > Random idea: Could this additional information (and I guess the code > that uses it too) be moved out to a loadable module? > > The obvious limitation would be that the user would need to have the > module loaded for the decoding to work, but that could be worked > around by marking it for autoload when a crash is noticed the first > time and then getting a better report the second time. IMHO that's too big of a disadvantage. Many crashes are rare and either you have this always enabled, or you missed your only chance. > Best, > Tomasz >