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 21C96390219; Thu, 14 May 2026 10:16:43 +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=1778753804; cv=none; b=BuslCaV+fPPkSDFm65WSBphx+GO0tdeGkq6UMkv49EVMcqRBCDe/itqHrCon48HFwpr/c1V9HYdukkN8ikxMszdvxelrPPI8xtGOGPExoO3zP1IGkFQdlaJQH9twQJNS0J6wVSh7K1AKqusNojhJvlSRccjZqsO97UPJcfx0IGw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778753804; c=relaxed/simple; bh=3xrLp236XQGoz49u8uCprVRlNKE6+kM1ULNPYfoql+U=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=MpsHlAKlJbFVmZgitBhew00Fc3XPQ6fkIKn4hy3EjnhkCQpSrnPOq9VHAH+XnCNiLk9Z+GT9AfgckvpztcrRjxG0PXt0g2JmBqVgtmq86tVF57HHnqku1zhPgpjgDT2s+yXjSRSh1j6pGEgyk8wL1ozrpbrlD4r0fQ+sP9Zjc/0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=lMYdSMym; 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="lMYdSMym" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4515DC2BCB3; Thu, 14 May 2026 10:16:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1778753803; bh=3xrLp236XQGoz49u8uCprVRlNKE6+kM1ULNPYfoql+U=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=lMYdSMymthkPfomjmUqehGXi82PqxU0g4S9rSs7m/t/EQAblvxuep3lMks9m6nRdj LRcbSgxfno0FsyYjmbwdh4AJSJ3/N64izDlpSPkQ2DkakbEKCMNvb3RrLCfQo0+Jv2 Rl9j1eYt2uffbhTXqTvZTXWEVctfhUa3JASfMBRw= Date: Thu, 14 May 2026 12:16:48 +0200 From: Greg KH To: Jianlin Lv Cc: corbet@lwn.net, skhan@linuxfoundation.org, rafael@kernel.org, dakr@kernel.org, jianlv@ebay.com, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, driver-core@lists.linux.dev Subject: Re: [PATCH] driver core: Add cmdline option to force probe type Message-ID: <2026051443-exuberant-important-534f@gregkh> References: <20260514094955.76305-1-jianlv@ebay.com> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260514094955.76305-1-jianlv@ebay.com> On Thu, May 14, 2026 at 05:49:55PM +0800, Jianlin Lv wrote: > From: Jianlin Lv > > Device drivers that use asynchronous probing can cause non-deterministic > device ordering and naming across reboots. A typical example is storage > drivers (like sd/nvme): asynchronous probing can lead to inconsistent disk > logical names after reboot. In scenarios where disk naming consistency is > critical, the probe type should be set to synchronous. > > This patch introduces a driver_probe kernel parameter that overrides any > driver's hard-coded probe type settings and allows runtime control without > requiring kernel recompilation: > > driver_probe=PROBE_TYPE_SYNC,nvme,sd # Force specific drivers sync > driver_probe=PROBE_TYPE_ASYNC,*,usb # Force all async except usb > driver_probe=PROBE_TYPE_SYNC,* # Force all drivers synchronous > > The implementation replaces the limited driver_async_probe parameter with > a more flexible interface that can force either synchronous or asynchronous > probing as needed. > > Signed-off-by: Jianlin Lv > --- > .../admin-guide/kernel-parameters.txt | 27 +++++-- > drivers/base/dd.c | 71 ++++++++++++++----- > 2 files changed, 74 insertions(+), 24 deletions(-) > > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > index 4d0f545fb3ec..b43a8bd20356 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -1377,12 +1377,27 @@ Kernel parameters > it becomes active and is searched during signature > verification. > > - driver_async_probe= [KNL] > - List of driver names to be probed asynchronously. * > - matches with all driver names. If * is specified, the > - rest of the listed driver names are those that will NOT > - match the *. > - Format: ,... You can not remove an existing user/kernel api, sorry, that is not allowed as you just broke all systems that were relying on this :( thanks, greg k-h