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 918DE263F44 for ; Tue, 17 Feb 2026 08:10:51 +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=1771315851; cv=none; b=tLnLEGcGntzsF/NR9yueyQFblCXW7y7m7I2s2bu6evgAY51/gUUMtdOijiz9G1PgXAgVCynklVX4JQYmwAbVLRFwb8H2aUsEN5SGaFMGCu/aUHeCC7VU9j6baUb4gkbejrMd0PSSSCETijdHUjjICLt3Efjg6k53O8wle3drvg8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771315851; c=relaxed/simple; bh=c9RrN16ENka2bmhup2I3IYc94x2FdV4nR1nj/uZkQi4=; h=MIME-Version:Date:From:To:Cc:Message-Id:In-Reply-To:References: Subject:Content-Type; b=HCWyaOJfeIGlRrzDpQowNwzc9bz1iDrEay1pe1cMqvsmtVSFlFfow3lm/s3tJzpJbH1qXRFwRYlENHACaWXFf1ZE/QyUkWLqAnh5rGa4Cvjr4rQ1oZNXzTFIznrgTwynZ6Y3/LYwsR8rP8MBB9+IuQRQrcHJh1Q/LbEVprf1o2s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=VEFLPw2w; 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="VEFLPw2w" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 187E0C4CEF7; Tue, 17 Feb 2026 08:10:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1771315851; bh=c9RrN16ENka2bmhup2I3IYc94x2FdV4nR1nj/uZkQi4=; h=Date:From:To:Cc:In-Reply-To:References:Subject:From; b=VEFLPw2wCCG2u/cUm10oLr8SG9B6/+Tn2/aQlIwm6eldGulzFRZxKpHWlXQUHLdJ0 oummYyuiNGn+WKw34GE4QdHgoTzmIkacSlOKtZhHzVRXxk4hWPWUlTwBRAwjaHpSVP Oabn+to9epPmOWSJWPACggTbzY559DUU+p2W4vA1cMuVq7FtfKoYp5Gjl6L+Z0KzKA S98HfNuTh2GrKuZOSkil5HCkSUNbCMUfoSSdsjhDhps0Ybno2ZTlmBTSfTW+XBRZAF w/VbVs7yfuvvMnUnllNRa6CGN+Oi8uOJrrRfHhiyoK95UrX7243ZEBGkx6fxXv0o6m 8eSsDW6pY8AjQ== Received: from phl-compute-01.internal (phl-compute-01.internal [10.202.2.41]) by mailfauth.phl.internal (Postfix) with ESMTP id 05431F4006A; Tue, 17 Feb 2026 03:10:50 -0500 (EST) Received: from phl-imap-02 ([10.202.2.81]) by phl-compute-01.internal (MEProxy); Tue, 17 Feb 2026 03:10:50 -0500 X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeefgedrtddtgddvudelvdegucetufdoteggodetrf dotffvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfurfetoffkrfgpnffqhgenuceu rghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmnecujf gurhepofggfffhvfevkfgjfhfutgfgsehtjeertdertddtnecuhfhrohhmpedftehrugcu uehivghshhgvuhhvvghlfdcuoegrrhgusgeskhgvrhhnvghlrdhorhhgqeenucggtffrrg htthgvrhhnpedvueehiedtvedtleekuddutefgffdtleetfeetveejveejieehfefhjeei jeefudenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmhgrihhlfhhrohhmpe grrhguodhmvghsmhhtphgruhhthhhpvghrshhonhgrlhhithihqdduieejtdehtddtjeel qdeffedvudeigeduhedqrghruggspeepkhgvrhhnvghlrdhorhhgseifohhrkhhofhgrrh gurdgtohhmpdhnsggprhgtphhtthhopeehpdhmohguvgepshhmthhpohhuthdprhgtphht thhopeigkeeisehkvghrnhgvlhdrohhrghdprhgtphhtthhopehkvgigvggtsehlihhsth hsrdhinhhfrhgruggvrggurdhorhhgpdhrtghpthhtohepugihohhunhhgsehrvgguhhgr thdrtghomhdprhgtphhtthhopehlihhnuhigqdgvfhhisehvghgvrhdrkhgvrhhnvghlrd horhhgpdhrtghpthhtoheplhhinhhugidqkhgvrhhnvghlsehvghgvrhdrkhgvrhhnvghl rdhorhhg X-ME-Proxy: Feedback-ID: ice86485a:Fastmail Received: by mailuser.phl.internal (Postfix, from userid 501) id D4C80700065; Tue, 17 Feb 2026 03:10:49 -0500 (EST) X-Mailer: MessagingEngine.com Webmail Interface Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ThreadId: AR4vd3DIDa3F Date: Tue, 17 Feb 2026 09:10:28 +0100 From: "Ard Biesheuvel" To: "Dave Young" Cc: linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, kexec@lists.infradead.org, x86@kernel.org Message-Id: <824bf9d5-93d3-4791-a064-3852014a1264@app.fastmail.com> In-Reply-To: References: Subject: Re: [PATCH] efi/x86-stub: store acpi_rsdp_addr in bootparams Content-Type: text/plain Content-Transfer-Encoding: 7bit Hi Dave, On Tue, 17 Feb 2026, at 09:04, Dave Young wrote: > Kernel panic occurs during a kexec reboot when EFI runtime services > are not enabled in the first kernel. The issue is that the second > kernel cannot find the ACPI RSDP address during boot. > > In legacy boot, the acpi_rsdp_addr is set in early x86 boot code. > However, kernel decompression has moved to the EFI stub for EFI boot. > Therefore, the x86 EFI stub must also be updated to store the > acpi_rsdp_addr in the boot parameters to ensure the kexec kernel > can find it. > > (Note: If the pre-kexec kernel was itself a kexec boot, the later kexec > reboot will still utilize the legacy decompressor path, so the original > code remains functional though some cleanups can be done later.) > > Signed-off-by: Dave Young > --- > drivers/firmware/efi/libstub/x86-stub.c | 18 ++++++++++++++++++ > 1 file changed, 18 insertions(+) > If this issue is kexec-specific, can we move this to where the kexec code prepares the boot_params struct for the next kernel?