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 7DA4616A387; Mon, 27 May 2024 15:55:06 +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=1716825306; cv=none; b=Gm5F7VPv32Id13ZFiJiPkZuNuIEnwwQ+jeChLFrlc1xVwldamwGmpgMG/lrphyeud59pHZEg4DXv/qnHaBScnPVZqru2EtPNQa+L4S+HfD84zoKFWVf0/9JlpyONYnrZ54GYryM4Ksbbs/Rs2sTJ7CF7I4LgtJ9OZ4Q5dljkjUw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716825306; c=relaxed/simple; bh=9O1/9N+pW9u9GQ2iwg/POokNTzd/48jaP6RProOYYSk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=dGnUgAyeFZWPX653IiP7XGuyvS5MEKDu6o/lKYJ95wI2TgdOw95qN2wloB5uP0BC3pw8LffYCOdF4xNdzc1sJ4BIY+vuMTgexSgfzDKoMXG5NmjmKFRdjTNSjk7sUFbmjVC7MTtAjfFFmeNb/5tZ7fYhBry09OOJAYzG0SP6+zs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=EbaCyU8C; 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="EbaCyU8C" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E9FBDC4AF08; Mon, 27 May 2024 15:55:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1716825306; bh=9O1/9N+pW9u9GQ2iwg/POokNTzd/48jaP6RProOYYSk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EbaCyU8CFYAegLD2d0CkQjzTNpEHjCjVYZxq+L24lnJSiwDOhAw3pPltr8hLZ0sVp 4b31dqPVYpoAu+mSZLJu2VM3JV+tqI56o/4UQNbitwFrHSNaMNgbM2AMtN9GjJdEML i8ndNotM1XlsIEaj1NgnkterdGrLSGXo0VH0YENSVp3oD9gQCyk4WDvXZnndz5k+e0 9YGRKn0iI3TodUOMEEpUj7ihhppGBWvJhdumDKponBrD5BiF/pK5aOWnHMb82JC4Lx YLijDS8L8TRJzIPpMRrybzr7LlZMhdvwujs7vFqW+yje/Kd+Ivxs1zu/t/5FAZ0Ojn 4YoVSszSU1dZA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Ben Fradella , Andy Shevchenko , Klara Modin , Shin'ichiro Kawasaki , Hans de Goede , Sasha Levin , ilpo.jarvinen@linux.intel.com, platform-driver-x86@vger.kernel.org Subject: [PATCH AUTOSEL 6.8 20/20] platform/x86: p2sb: Don't init until unassigned resources have been assigned Date: Mon, 27 May 2024 11:53:03 -0400 Message-ID: <20240527155349.3864778-20-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240527155349.3864778-1-sashal@kernel.org> References: <20240527155349.3864778-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.8.11 Content-Transfer-Encoding: 8bit From: Ben Fradella [ Upstream commit 2c6370e6607663fc5fa0fd9ed58e2e01014898c7 ] The P2SB could get an invalid BAR from the BIOS, and that won't be fixed up until pcibios_assign_resources(), which is an fs_initcall(). - Move p2sb_fs_init() to an fs_initcall_sync(). This is still early enough to avoid a race with any dependent drivers. - Add a check for IORESOURCE_UNSET in p2sb_valid_resource() to catch unset BARs going forward. - Return error values from p2sb_fs_init() so that the 'initcall_debug' cmdline arg provides useful data. Signed-off-by: Ben Fradella Acked-by: Andy Shevchenko Tested-by: Klara Modin Reviewed-by: Shin'ichiro Kawasaki Link: https://lore.kernel.org/r/20240509164905.41016-1-bcfradella@proton.me Reviewed-by: Hans de Goede Signed-off-by: Hans de Goede Signed-off-by: Sasha Levin --- drivers/platform/x86/p2sb.c | 29 +++++++++++++++-------------- 1 file changed, 15 insertions(+), 14 deletions(-) diff --git a/drivers/platform/x86/p2sb.c b/drivers/platform/x86/p2sb.c index 3d66e1d4eb1f5..1ac30034f3e59 100644 --- a/drivers/platform/x86/p2sb.c +++ b/drivers/platform/x86/p2sb.c @@ -56,12 +56,9 @@ static int p2sb_get_devfn(unsigned int *devfn) return 0; } -static bool p2sb_valid_resource(struct resource *res) +static bool p2sb_valid_resource(const struct resource *res) { - if (res->flags) - return true; - - return false; + return res->flags & ~IORESOURCE_UNSET; } /* Copy resource from the first BAR of the device in question */ @@ -220,16 +217,20 @@ EXPORT_SYMBOL_GPL(p2sb_bar); static int __init p2sb_fs_init(void) { - p2sb_cache_resources(); - return 0; + return p2sb_cache_resources(); } /* - * pci_rescan_remove_lock to avoid access to unhidden P2SB devices can - * not be locked in sysfs pci bus rescan path because of deadlock. To - * avoid the deadlock, access to P2SB devices with the lock at an early - * step in kernel initialization and cache required resources. This - * should happen after subsys_initcall which initializes PCI subsystem - * and before device_initcall which requires P2SB resources. + * pci_rescan_remove_lock() can not be locked in sysfs PCI bus rescan path + * because of deadlock. To avoid the deadlock, access P2SB devices with the lock + * at an early step in kernel initialization and cache required resources. + * + * We want to run as early as possible. If the P2SB was assigned a bad BAR, + * we'll need to wait on pcibios_assign_resources() to fix it. So, our list of + * initcall dependencies looks something like this: + * + * ... + * subsys_initcall (pci_subsys_init) + * fs_initcall (pcibios_assign_resources) */ -fs_initcall(p2sb_fs_init); +fs_initcall_sync(p2sb_fs_init); -- 2.43.0