From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 0A138D49C9B for ; Fri, 30 Jan 2026 10:25:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=kD5Mgj9t9wawb46QR0zdGGuw88JGve+LVQ5Rg9kqKDY=; b=QWN3OfJSLR6PpsL7TC2z01fKe+ 0koDPnchEr0EP0ROsRGtGO0KmXJaYNDr7K2LYxEm+X1s8fiKdqlpsvP4mBVPw6vtPJLsIlwWm5+cO SbXyLszdK3Qh2sLW3UpCHcksnLX4yq5Bzjzo6L0eCY4c6SKS2J4UzZb1vT2yT6xecgzg6z1NeDKqG rJ1f4FMCSucQs4X8M7QSJSKdUWWkkdCer/YQOa6vEg1Pz+zARa+wZz18bo+Ww9Vl++Ia0PlzB3Zqx BiX8jxOw+so3tn89WN4Xf3Q+c3CVNnzPPlcTqHShZLn5K8C9IHwPdP3l3i0gTQwlPZd38AVuhiNkS A07qheIg==; 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charset=us-ascii Content-Disposition: inline In-Reply-To: X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hello Grimmauld, On Thu, Jan 29, 2026 at 03:06:59PM +0100, Grimmauld wrote: > Hello Anand, > > I have tested this patch. > Hardware/Kernel information: > - radxa rock 5c lite > - rk3588s CPU, arm64 > - defconfig NixOS kernel > - picked onto 6.18.7 > - DT: rockchip/rk3588s-rock-5c.dtb > - tested both uboot (mainline) and edk2 (vendor) > > On Fri, Aug 09, 2024 at 01:06:09PM +0530, Anand Moon wrote: > > Rockchip DWC PCIe driver currently waits for the combo PHY link > > (PCIe 3.0, PCIe 2.0, and SATA 3.0) to be established link training > > during boot, it also waits for the link to be up, which could consume > > several milliseconds during boot. > > I found that without this patch, USB 3 ports as well as the PCIe connector seemingly stay uninitialized during boot on my hardware. > This manifests in a bootable USB flash drive loading initrd from bootloader (both uboot and edk2) perfectly, but then fails to mount the rootfs from the drive. > In effect, boot is not just slower than it should be, it just does not boot all the way at all. > In that scenario, the devfs entries corresponding to the flash drive are simply missing, same for the sysfs where i would expect the USB device listed. > Replugging the USB flash drive during initrd does seem to fix that, but is tedious and not viable for a server. > Similarly, booting from m.2 SSD attached via PCIe fails the same way, with rootfs timing out despite the bootloader correctly reading initrd on the same drive. > Fwiw, replugging the SSD does not work like it does for USB flash drives, and is even worse of an idea. > USB 2 ports as well as SD card boots correctly, even without your patch. > Without your patch, i am seeing "deferred probe pending" in dmesg before boot gets stuck, which was the hint which made me find your patch. > I am not sure whether that is the actual cause or just a symptom for why drives are not recognized during boot, and am not quite sure how to debug this further. > > > To optimize boot time, this commit allows asynchronous probing. > > This change enables the PCIe link establishment to occur in the > > background while other devices are being probed. > > With this patch, booting from SSD or USB 3 port works flawlessly, and i have not seen any regressions with SD card or USB 2 boot, nor any other hardware component. > This setup has worked for multiple boots without fail, both with traditional ext4 and zfs rootfs being loaded from USB 3 and PCIe. > Because i require this patch to run my rock 5c from SSD, i am currently running a custom patched kernel, but would highly appreciate this patch making its way to mainline eventually. > There might well be something else going on here. The proposed patch may not be the "proper" fix to the issues i am seeing, but it does at least work. > > I have NOT tested boot from eMMC (either with or without this patch), though i have no reason to believe it would be impacted. > > I am happy to provide more info as needed. First time posting to the LKML, i hope i am doing this right... > > Tested-by: Grimmauld I tested this patch again on the latest kernel, and it still results in the "requesting loading a module with wait allowed while being called from async context can result in a deadlock" warning from the modules code. (With the calling code being phylib.) See the phylib splat that I previously reported in this thread. Note that I've built the network PHY driver that phylib wants to load (CONFIG_REALTEK_PHY=y) as built-in. As long as the PHY driver is built as built-in, I don't think that the problem the modules code is warning about can happen. (But I also don't understand why it is trying to load a module when the driver is built as built-in in the first place...) Anyway, my networking is working perfectly fine even with the splat. Having async probing for the Rockchip PCIe controller driver, which is used a LOT of rockchip based SoCs, is a good thing, so I don't think it is right to avoid enabling async probing just because it results in a splat on a single rockchip based board (rock5b). Kind regards, Niklas