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 5B4B3287248; Thu, 10 Jul 2025 06:41:37 +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=1752129698; cv=none; b=B0LDSLUTyYkTVLCdmTa5BUNMWPvqLS9Jym2v9XXTVjBEMxqaw0yUtWcSxdZiMrGB/Kzq2x+byY06h3+At4yjghWde2MP/87cOc+4QovPzrBcHeD9DF1dKGmuknjX4FNu1MmgpW4stzhXaSdrpqYf+yzLJp5gAkPmi3eZjxXUrtk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752129698; c=relaxed/simple; bh=we/ipfwmIbO428HHSc8m/3FIlkhp1xYcQZObCY7CDiA=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=lDy6JIYN5d0ll3MSb9lDT3lnF3z36ozSMYyktXFbzyMmu1sNLEkHwqZLvhSEj0d6XlBAhoJ6grdX5fa+2Z1CvpkumqLZQM2zTy3nGTtHdg/Mx1kNm1sHyEfekGzdE1NxJkDAuxJKsXWERRhk2mEGfJDdc/kJmc9Q1khEf+sVIWM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=HO9HyGOv; 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="HO9HyGOv" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B5E17C4CEF5; Thu, 10 Jul 2025 06:41:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1752129697; bh=we/ipfwmIbO428HHSc8m/3FIlkhp1xYcQZObCY7CDiA=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=HO9HyGOvh2mfGdR/wLBBPJGQ51LC0H6mL+gC8J1TWcOspG1wYxTPXCzYiNMePrQmy NcbrXJS4I7UPc3tgT6/FPbiBqvhSmabLABbhSqSbpFeYpIQeK0g12r1IUooUmb++w/ tGYllWtnfj3ZUynq5L2zVlR1aCs7JOjXcZ8dpvkgY+NuTw3Ej7HVe4/tXi+qI/X3m/ i0Irl7+6b5dtscboPwG6+Qt/SXKQ5tEYsjoScIlXxbequCLTXy1n21fUpfknXJhXyd s+hnBvbTwImHC2LGrjO4n/MazQImT6uaeFium4X3bUJ7P3VGTpQeMedDo4cuy8FGzm nhSmCy8a4bsmA== Message-ID: Date: Thu, 10 Jul 2025 08:41:34 +0200 Precedence: bulk X-Mailing-List: linux-efi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] efi: add ovmf debug log driver To: Ard Biesheuvel Cc: Gerd Hoffmann , linux-efi@vger.kernel.org, open list References: <20250708125624.734132-1-kraxel@redhat.com> <6edfa099-ab0c-41f6-89ea-0fd67666dd05@kernel.org> <2mn65slwkwmjpeilma2isw7zgabdmda4rhpqjiutwdwqno2wrh@zghymlce2fiy> <8621135e-445a-42dd-89e0-bf8fc3e2b6b7@kernel.org> <4cix3k4h32wozt3nxic5un7jyzfjrmqmzbzmtr3ivw5b2bz363@mw6bke7w4oaq> <5800c426-95fd-4a81-b979-c0bc2bc293dd@kernel.org> From: Krzysztof Kozlowski Content-Language: en-US Autocrypt: addr=krzk@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 10/07/2025 01:14, Ard Biesheuvel wrote: > On Thu, 10 Jul 2025 at 00:39, Krzysztof Kozlowski wrote: >> >> On 09/07/2025 16:31, Gerd Hoffmann wrote: >>> On Wed, Jul 09, 2025 at 04:20:49PM +0200, Krzysztof Kozlowski wrote: >>>> On 09/07/2025 16:17, Gerd Hoffmann wrote: >>>>> On Wed, Jul 09, 2025 at 03:58:58PM +0200, Krzysztof Kozlowski wrote: >>>>>> On 08/07/2025 14:56, Gerd Hoffmann wrote: >>>>>>> +MODULE_DESCRIPTION("OVMF debug log"); >>>>>>> +MODULE_AUTHOR("Gerd Hoffmann "); >>>>>>> +MODULE_LICENSE("GPL"); >>>>>>> +MODULE_ALIAS("platform:ovmf_debug_log"); >>>>>>> diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig >>>>>>> index db8c5c03d3a2..ac0a03ec3452 100644 >>>>>>> --- a/drivers/firmware/efi/Kconfig >>>>>>> +++ b/drivers/firmware/efi/Kconfig >>>>>>> @@ -263,6 +263,14 @@ config EFI_COCO_SECRET >>>>>>> virt/coco/efi_secret module to access the secrets, which in turn >>>>>>> allows userspace programs to access the injected secrets. >>>>>>> >>>>>>> +config OVMF_DEBUG_LOG >>>>>>> + tristate "Expose OVMF firmware debug log via sysfs" >>>>>>> + depends on EFI >>>>>>> + help >>>>>>> + Recent OVMF versions (edk2-stable202508 + newer) can write >>>>>>> + their debug log to a memory buffer. This driver exposes the >>>>>>> + log content via sysfs (/sys/firmware/efi/ovmf_debug_log). >>>>>> >>>>>> Where did you document new ABI? >>>>> >>>>> The log buffer header struct is documented in the header file for the >>>>> edk2 code: >>>>> https://github.com/tianocore/edk2/blob/master/OvmfPkg/Include/Library/MemDebugLogLib.h >>>> >>>> You added a new sysfs interface. I meant documentation for this. >>> >>> The sysfs file contains the log and you can simply use >>> 'cat /sys/firmware/efi/ovmf_debug_log' to read it. >> >> Don't explain how it works to me. I did not ask how it works. I asked >> where is the new ABI documented? >> > > Please drop the condescending tone, and don't make people guess at > what you are trying to say. > > If you meant to say that the patch lacks an ABI description in > Documentation/ABI, then you are absolutely right, and you can just say > so. Maybe it was documented already, so I asked where ABI is documented. I think this was exactly what you said here - Documentation/ABI: "Where did you document new ABI?" Best regards, Krzysztof