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 2346333A712; Fri, 9 Jan 2026 12:53:04 +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=1767963184; cv=none; b=Vf1JLziG2uJT/AKgwDPDalcChfDNHDHjjT3jPOhkGBv7EbR2KBQtZEyDhgWqyE+9nfd9rYl4k8ZfVJ3NDxjKRyjjnPRJJKg1G/iW4XsjVTieP6FkGBScoXZbVPr6lMXayaFh/sQacGrFpwvg7pF6ehg36136Ove5ILh15Ynqb7s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767963184; c=relaxed/simple; bh=45skOZP3E1FMp4vNKY8mPQiOaIh2HirSP5nOvofdglQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=amhob2gN4ymGglbdR16ELLrYtoCUcGBbUn5Twm/SneI+uHVVcUxXEz19Szxy7fDoGXpnvK+SB8VU13b8Rgfe2b2CZo6Z8591CJ0tpiLBqz7rqKfxGBdgyNrBmN2CyoZFDF8L690XSlWl0Z/GZDkoRgP8PiHB8p0SSjg/T/qg798= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=sRiIMI2g; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="sRiIMI2g" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A4202C4CEF1; Fri, 9 Jan 2026 12:53:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1767963184; bh=45skOZP3E1FMp4vNKY8mPQiOaIh2HirSP5nOvofdglQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sRiIMI2gniy3YGuy1UiUXX2ytOPWHprsUMETsjb7daRNOQ9avkmLiRfk2XIg9FlEh 0bzS7wgEUziIBs5998U0p3FPtLK3JdfQodAMDSCLR5YPvaP1TKRX/P9VJRsqF0QKVm lTIRwEQ+31OFwL3RkubD7Kxpe8CSWQLwdxJf+iWU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ashish Kalra , Vasant Hegde , Sairaj Kodilkar , Joerg Roedel , Sasha Levin Subject: [PATCH 6.1 625/634] Revert "iommu/amd: Skip enabling command/event buffers for kdump" Date: Fri, 9 Jan 2026 12:45:03 +0100 Message-ID: <20260109112141.155967308@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260109112117.407257400@linuxfoundation.org> References: <20260109112117.407257400@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Greg Kroah-Hartman This reverts commit f33890f95140660923003ba1e2f114dee20e691b which is commit 9be15fbfc6c5c89c22cf6e209f66ea43ee0e58bb upstream. This causes problems in older kernel trees as SNP host kdump is not supported in them, so drop it from the stable branches. Reported-by: Ashish Kalra Link: https://lore.kernel.org/r/dacdff7f-0606-4ed5-b056-2de564404d51@amd.com Cc: Vasant Hegde Cc: Sairaj Kodilkar Cc: Joerg Roedel Cc: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/iommu/amd/init.c | 28 +++++++++------------------- 1 file changed, 9 insertions(+), 19 deletions(-) --- a/drivers/iommu/amd/init.c +++ b/drivers/iommu/amd/init.c @@ -805,16 +805,11 @@ static void iommu_enable_command_buffer( BUG_ON(iommu->cmd_buf == NULL); - if (!is_kdump_kernel()) { - /* - * Command buffer is re-used for kdump kernel and setting - * of MMIO register is not required. - */ - entry = iommu_virt_to_phys(iommu->cmd_buf); - entry |= MMIO_CMD_SIZE_512; - memcpy_toio(iommu->mmio_base + MMIO_CMD_BUF_OFFSET, - &entry, sizeof(entry)); - } + entry = iommu_virt_to_phys(iommu->cmd_buf); + entry |= MMIO_CMD_SIZE_512; + + memcpy_toio(iommu->mmio_base + MMIO_CMD_BUF_OFFSET, + &entry, sizeof(entry)); amd_iommu_reset_cmd_buffer(iommu); } @@ -863,15 +858,10 @@ static void iommu_enable_event_buffer(st BUG_ON(iommu->evt_buf == NULL); - if (!is_kdump_kernel()) { - /* - * Event buffer is re-used for kdump kernel and setting - * of MMIO register is not required. - */ - entry = iommu_virt_to_phys(iommu->evt_buf) | EVT_LEN_MASK; - memcpy_toio(iommu->mmio_base + MMIO_EVT_BUF_OFFSET, - &entry, sizeof(entry)); - } + entry = iommu_virt_to_phys(iommu->evt_buf) | EVT_LEN_MASK; + + memcpy_toio(iommu->mmio_base + MMIO_EVT_BUF_OFFSET, + &entry, sizeof(entry)); /* set head and tail to zero manually */ writel(0x00, iommu->mmio_base + MMIO_EVT_HEAD_OFFSET);