From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-dl1-f42.google.com (mail-dl1-f42.google.com [74.125.82.42]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2D9F33DDDA8 for ; Tue, 19 May 2026 07:58:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.82.42 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779177497; cv=none; b=YvpdUNWFr+YRz3ZqGkjNmytv+sryhwuzr+02LLTUubeo+t8aqDa6qqYUwF8akRdVEbdCsSJo/7lEjFilYzGzgXIWjv9C764Tfs9v/IKmPQYqZPEL+RF9c7qA0WgjIbuTKGM3+ActHP89ZyHQCMG4qtA9by5IpsWz5WLojuY9E+k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779177497; c=relaxed/simple; bh=TZ0RN3qnNzUPKYI6sc0z1cZ1dFrGqG8XGPMWNd6bguI=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=dP/Ysa8SpjLIDLEIGNcNjO+W/AFPyDDiaePig8hvE1XL3YRgHhtybPwR8Lqi5MH1bkm0bcOlr8ZiwlUfRvIjhqOoINJK5IVg1Tnn2SF/8v3WckHvfmsfz7UdspkIbqfVojoVSdl2saJoyJEyFDTVaVa8avJM2K8GHqJACCwm/j4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=e1euA8li; arc=none smtp.client-ip=74.125.82.42 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="e1euA8li" Received: by mail-dl1-f42.google.com with SMTP id a92af1059eb24-1309f4ee97fso3540664c88.1 for ; Tue, 19 May 2026 00:58:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1779177495; x=1779782295; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=q7SDGHJz2p+KDEC7XABBWobKGkDCgsLu+7qpYk+YyVw=; b=e1euA8liJfTas6XGCEwfGRgeH0xFXl1TXyU8XHoyoVJtYgt+U3LPLopyyE5z1vabhE Dy8XUl6yyikuNlZDiuJMlqtoEPdOyEo5fHgon2kOgEU9WnN28ZgxdphW2hxmBfy2JN7U lb4YmKG+gzJG4IoLHXWpMuHUysbkPsSWIPtg+7P7lnXnRS+AWshqwFn+ufxQ5C3jm8Ln YGJD4pbeu8KhLK+jGqo9J8QAWnwUGjANK5LG1Q2W0vRYD0mL1Dw70TiyFc132sHjm1k5 9NxeO+2xB9a3T+A2fFJ6F+54KsANN5We+5FguhE7uoL6gWmk5V3P7TzPb48+w7c+R67+ LZUQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1779177495; x=1779782295; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=q7SDGHJz2p+KDEC7XABBWobKGkDCgsLu+7qpYk+YyVw=; b=jwcjVFUui6zaoCJMTLycRBi9rmpGSuJKNcqwhbFGUMJfIkldze76c1uv828R40cCRR rODRbGYQ6gwl8hO9wo4ClyXfJW43hhaZZlee470iQmUJbKkA8PQwVWyb/Ih8hP+C8JnO 9OFn7K3JDB7k6J3wK+5EKj9/Hk2vlXGozTBGqLPpgmiDoHJtVSslg4u5PYYwhPdNPkMC cyB2xuRUpgwy7oTUoKE+YjdUzbHBShQTSm01SbtlrNql7ZX6P4nl8APM85oO8sSbn7xV T1JE/ZrYcADwWEFinUiSygaGnOSE4Z8oVYqNkU9aQeyfEensGL2LhjzaQKh5LpKe2HX4 3Zxg== X-Gm-Message-State: AOJu0YwgmOpG4jyIRJMLn2aPGSu6/hl0YfFwxnIyfby62SV5ACY3t/nh QZxbsVOmxm+wqW3R326naVfysj9b0tjUbWzHLp/3xwGNp7BV0PHpIFTU X-Gm-Gg: Acq92OGwEnu7jbTW+/Rp91MubGgOf81M0QCPPlKw6yAREP85OI9De37cvCK1UhGLuMJ n4wMa1hob1dYJFm/IR0+3SXFn5REhTgvHWbukoNQ06Hue4eE37iRbUv5ayWSjUUVvJOnzYaZ1ap Dn284BIgjSfom5yqIo2XHFC+oVxzDGPah/Zm3Fvr9jER5jH2zHpGnjP6pbKhFm+/Of9B31K2SOp 5495/W0AaeBICccTqywDiQm7ys5jzYL3BNRSC5Nm5TuyWr5y5RsEoM1ZPqY0A4O1qr6tDH3CNqC ZDNc/VCyerRDweXeqns57uzvug34mNux1FOpLYhCKw+eLyGVh6JaVApCe/TKhN/vUASPn/91wij Omy7EwNTR+swKE8efvwRwj+cEYls/3xMmABI6URRnQUWYJ36Fcm//LZCEYOiX2pE4pbMQFk2stE BXoSFWYPlL7BKoUxhOEJVV4CP5lADipjtVh4aN X-Received: by 2002:a05:7022:6082:b0:12b:f616:1a4e with SMTP id a92af1059eb24-13504740a2fmr7096626c88.23.1779177494893; Tue, 19 May 2026 00:58:14 -0700 (PDT) Received: from s7t7-debian-test.local ([67.170.89.46]) by smtp.gmail.com with ESMTPSA id a92af1059eb24-134cf44668asm18768901c88.6.2026.05.19.00.58.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 19 May 2026 00:58:14 -0700 (PDT) From: Tony Rodriguez To: davem@davemloft.net, sparclinux@vger.kernel.org Cc: linux-kernel@vger.kernel.org, andreas@gaisler.com, thuth@redhat.com, regressions@lists.linux.dev, glaubitz@physik.fu-berlin.de, unixpro1970@gmail.com Subject: [PATCH 0/1] sparc64: unify thread stack sizing and add explicit 32KB stack Date: Tue, 19 May 2026 00:57:54 -0700 Message-ID: <20260519075809.8993-1-unixpro1970@gmail.com> X-Mailer: git-send-email 2.53.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This patch fixes a reproducible stack exhaustion issue on SPARC64 that occurs during USB hub enumeration. This regression may have started sometime after kernel v6.12. With the default 16KB kernel stack, the following panic is triggered early in boot: [ 25.528399] Call Trace: [ 25.528403] [<0000000000433cd4>] dump_stack+0x8/0x18 [ 25.528419] [<00000000004297ac>] vpanic+0xdc/0x318 [ 25.528429] [<0000000000429a0c>] panic+0x24/0x30 [ 25.528436] [<0000000000be2280>] __schedule+0xa8/0x7bc [ 25.528445] [<0000000000be2b60>] schedule+0x24/0x4c [ 25.528452] [<0000000000be6970>] schedule_timeout+0xc8/0xe4 [ 25.528459] [<0000000000be3318>] __wait_for_common+0x78/0xf0 [ 25.528466] [<0000000000be3550>] wait_for_completion_timeout+0x1c/0x2c [ 25.528473] [<000000001005e2f4>] usb_start_wait_urb+0x68/0x128 [usbcore] [ 25.528502] [<000000001005e468>] usb_control_msg+0xb4/0xf8 [usbcore] [ 25.528518] [<0000000010051180>] set_port_feature+0x44/0x54 [usbcore] [ 25.528530] [<00000000100530f0>] hub_power_on+0xc8/0xe8 [usbcore] [ 25.528543] [<0000000010054fd8>] hub_activate+0x12c/0x644 [usbcore] [ 25.528557] [<0000000010059438>] hub_probe+0xdd4/0xeb0 [usbcore] [ 25.528570] [<0000000010062360>] usb_probe_interface+0x234/0x26c [usbcore] [ 25.528585] [<0000000000a10a40>] really_probe+0x1ac/0x3b0 This is caused by large SPARC64 trapframes, register-window spills, and deep call paths in usbcore. A 16KB stack is insufficient for this workload. The new logic is: SPARC64: THREAD_SIZE = 4 * PAGE_SIZE (32KB) THREAD_SHIFT = PAGE_SHIFT + 2 THREAD_SIZE_ORDER = 2 Non‑SPARC64 with PAGE_SHIFT == 13: Retains the existing 16KB stack behavior Fallback: Retains the existing 8KB stack behavior Signed-off-by: Tony Rodriguez Tony Rodriguez (1): sparc64: unify thread stack sizing and add explicit 32KB stack arch/sparc/include/asm/thread_info_64.h | 28 ++++++++++++------------- 1 file changed, 14 insertions(+), 14 deletions(-) -- 2.53.0