From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f177.google.com (mail-pl1-f177.google.com [209.85.214.177]) (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 CFFCB10F0 for ; Wed, 10 Jun 2026 08:37:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.177 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781080646; cv=none; b=VbDkibnFeQLgqj8MgHJVVl6aU9CriBQhU2yGh3P77S/s0dmsxLELd7sRV94oPinCI0XcSLczUDxYfRG/EcQMPr5HjG1GgcG5XzfXbqR9SWZMj9d+VnUYNsnGhohzNAeJRpjWlMHxd7dRVDuNI0ApZ1SDHVA0djRfqRd4PGYc3sc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781080646; c=relaxed/simple; bh=kaishit0l3D7M91kmsDJgwCJTTWfCGNoHd3rbC0bz6g=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=fyXo3yPq1xP+kkx48a2CFe73tu1DvOvJgbxorBnmGntpfxlz0hod8EzQjcrpChNqaiFztZOMI4Hl7lhkx2MkqL4VgXV1qxd0aj3pzWOm5zVqroBSWRBXm/rm3tTxjyN07Er+7ddAbn63cAo4RTRCG4i7NTHIiekN3NDToIVW/pI= 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=eFgucHH4; arc=none smtp.client-ip=209.85.214.177 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="eFgucHH4" Received: by mail-pl1-f177.google.com with SMTP id d9443c01a7336-2bf237e1433so71590905ad.1 for ; Wed, 10 Jun 2026 01:37:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1781080644; x=1781685444; 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=xTlLTPLQVob07Monee3VTFRy46RFeGt5gASHP+XGMa0=; b=eFgucHH4rRV+EM+SxB/B2YstHpe456xR5jOE0L6Syj36WHkQTPiSzbPvkJqSBm2jWk hdj5GMo2VqZgEU7YEKy4KOPFW2rQM4CnUyrEm0vEQ1ZYBdgKHfHpsyuF5/ZNptbjYWax v8KdYXKn91Fgg19uygQT3MJG7mLLNpzt+hx6SlbvH30KboUOAHHfFt9IZFO1uz1z/s4t wU3idruIMuS1J+CrNidgFvfPP1GDAX0YwrnzVbWidXWqAoRGzQi/69EFUOxNfjm94dEI i36DkXkRucrT8dl3QSs/BG+vWaJBkmsjAinhO/ckqKNA9r+nVI9Ya9Ab6ouUjUvlX1gS BGWw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1781080644; x=1781685444; 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=xTlLTPLQVob07Monee3VTFRy46RFeGt5gASHP+XGMa0=; b=CLEJCNK3H6pD+2kM+c8vJjqLhMKgAu4+51harpoTInC2QE0ygJKj2ogZzddgj02fgw v94LdEEaJUJsUOMPkx9e0V8GSES6g0lQNmbofivkuC54FbWKd1C9ejmd6mdT5Uc3uI7n zsFKoKeUeK08clmN7QV0z9Wttj/2OhuBJAer5gT6m9QSXhXwIEXiIgoXzzHJyQ5vIlso UT1fRjE9zX8P8Q5BfM/XQRIXNr/fUrEi/udUl6/ZHRJuGUzQHwNs4OmziOqmBrSoOrJV 8IU9l0OgktLzsg6hU9eyneR8Z80KD6Q632QoWjZHnrpMa0Y1p6AnpbwUEVBkPK8sWdWD nXSg== X-Gm-Message-State: AOJu0YxbCM4jFWH/BkJOKk8MXt7086huokGmUloPlfWASVlOzJcZjIYK ed+26zxarlsor2aWGm5hl2OJfdSZYrP6hkGf9SSpwC5kgSlOVK3kzL81Zw6IRhtZ X-Gm-Gg: Acq92OGDMRI8zzYYji7j+KcY4Zc4RURUWZioKcSLqgQ6yp4JIg3XV0/E7mm3Vj42D96 L5pSiwAaxQGSFM0KfcNurYCpswcs/vq4qljb3+FA/tzwa2t41efFO8e9kD+YzEPVBSzx6Rw9h2+ CMpEH2OoD3946NP5siOEgfIDop2sMZ2VHOr3gjn/YumfphXsVOrH5TPIN93DYecJm2YYbZH6ZdA 7zbVQj2wW5rnTPto7YJymzcmjrVQUDuSnJcgK4dPbex/RbzbRH5XFVuv+N92J72Omq+SlgoRDZw bfEUmYSFCuWadukaEBPDND8IzUZO0o5VjxScbiHOcLmyFJvfevlSqxuMB9PFpBGj2q53jQ1xVlO cn10e1QPA0aafh//fAN0z/Z0asliptYJXo+tLk1PgI+IMvX/odPfCziqKpUi6M6XLB0XsIkg0X9 SBHknqufAN9BZbYlh687/yhX8zgnX7zh/f287flqsr3qOUSCinw9PSt3aaDC1/Dd+X2/E8kB6jh 1BQ52GGvZlvzSfZng747PkTojkNQo59xIo9lcE3+z77rytjsswlTg5aNYPn6+Ies9c2HULlnQPI poy28BeuOIt/ptlwfEk= X-Received: by 2002:a17:903:90c:b0:2c0:b7e1:7f08 with SMTP id d9443c01a7336-2c1e859fc13mr290306175ad.28.1781080643939; Wed, 10 Jun 2026 01:37:23 -0700 (PDT) Received: from hardik-yoga.oryx-cobra.ts.net ([103.52.208.50]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2c164f8429fsm291897375ad.18.2026.06.10.01.37.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 10 Jun 2026 01:37:23 -0700 (PDT) From: Hardik Prakash To: linux-i2c@vger.kernel.org Cc: linux-gpio@vger.kernel.org, wsa@kernel.org, andriy.shevchenko@intel.com, mario.limonciello@amd.com, brgl@bgdev.pl, basavaraj.natikar@amd.com, linusw@kernel.org, nathan@kernel.org, chaitanya.kumar.borah@intel.com, Hardik Prakash Subject: [PATCH] Revert "i2c: designware: defer probe if child GpioInt controllers are not bound" Date: Wed, 10 Jun 2026 14:07:01 +0530 Message-ID: <20260610083701.18663-1-hardikprakash.official@gmail.com> X-Mailer: git-send-email 2.54.0 Precedence: bulk X-Mailing-List: linux-i2c@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit This reverts commit ef76a3a28c79b628890431aa344af633e892035b. The patch causes boot regressions on multiple machines. A NULL pointer dereference occurs when agpio->resource_source.string_ptr is NULL (i.e. when string_length is 0), and a probe deferral loop causes CPU starvation leading to kernel panic on Intel CI machines. The patch needs a proper rewrite addressing these issues before resubmission. Reported-by: Nathan Chancellor Reported-by: Borah, Chaitanya Kumar Signed-off-by: Hardik Prakash --- drivers/i2c/busses/i2c-designware-platdrv.c | 156 -------------------- 1 file changed, 156 deletions(-) diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c index 1c01b0460385..3351c4a9ef11 100644 --- a/drivers/i2c/busses/i2c-designware-platdrv.c +++ b/drivers/i2c/busses/i2c-designware-platdrv.c @@ -8,8 +8,6 @@ * Copyright (C) 2007 MontaVista Software Inc. * Copyright (C) 2009 Provigent Ltd. */ - -#include #include #include #include @@ -132,152 +130,6 @@ static int i2c_dw_probe_lock_support(struct dw_i2c_dev *dev) return 0; } -#ifdef CONFIG_ACPI -struct gpio_dep_ctx { - struct list_head gpio_controllers; - int ret; -}; - -struct gpio_controller_ref { - struct list_head node; - char *path; -}; - -static int check_gpioint_resource(struct acpi_resource *ares, void *data) -{ - struct gpio_dep_ctx *ctx = data; - struct acpi_resource_gpio *agpio; - struct gpio_controller_ref *ref, *tmp; - bool found = false; - - if (ares->type != ACPI_RESOURCE_TYPE_GPIO) - return 1; - - agpio = &ares->data.gpio; - if (agpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_INT) - return 1; - - /* Check if we've already tracked this GPIO controller */ - list_for_each_entry(tmp, &ctx->gpio_controllers, node) { - if (!strcmp(tmp->path, agpio->resource_source.string_ptr)) { - found = true; - break; - } - } - - if (!found) { - ref = kzalloc(sizeof(*ref), GFP_KERNEL); - if (!ref) { - ctx->ret = -ENOMEM; - return 0; - } - - ref->path = kstrdup(agpio->resource_source.string_ptr, GFP_KERNEL); - if (!ref->path) { - kfree(ref); - ctx->ret = -ENOMEM; - return 0; - } - - list_add_tail(&ref->node, &ctx->gpio_controllers); - } - - return 1; -} - -static int check_child_gpioint(struct acpi_device *adev, void *data) -{ - struct gpio_dep_ctx *ctx = data; - struct list_head res_list; - - INIT_LIST_HEAD(&res_list); - - acpi_dev_get_resources(adev, &res_list, check_gpioint_resource, ctx); - acpi_dev_free_resource_list(&res_list); - - if (ctx->ret < 0) - return ctx->ret; - - return 0; -} - -static int i2c_dw_check_gpio_dependencies(struct device *dev) -{ - struct acpi_device *adev = ACPI_COMPANION(dev); - struct gpio_dep_ctx ctx = { .ret = 0 }; - struct gpio_controller_ref *ref, *tmp; - int ret = 0; - - if (!adev) - return 0; - - INIT_LIST_HEAD(&ctx.gpio_controllers); - - /* Walk all child devices and collect GpioInt controller references */ - ret = acpi_dev_for_each_child(adev, check_child_gpioint, &ctx); - if (ret < 0 || ctx.ret < 0) { - ret = ctx.ret ?: ret; - goto cleanup; - } - - /* For each GPIO controller, check if its parent device is bound */ - list_for_each_entry(ref, &ctx.gpio_controllers, node) { - acpi_handle handle; - acpi_status status; - struct acpi_device *gpio_adev; - struct device *gpio_dev; - bool bound; - - status = acpi_get_handle(NULL, ref->path, &handle); - if (ACPI_FAILURE(status)) - continue; - - gpio_adev = acpi_fetch_acpi_dev(handle); - if (!gpio_adev) - continue; - - gpio_dev = acpi_get_first_physical_node(gpio_adev); - acpi_dev_put(gpio_adev); - - if (!gpio_dev) { - ret = -EPROBE_DEFER; - goto cleanup; - } - - /* - * Check if the GPIO controller's device is bound. If not, - * defer probe to ensure GPIO initialization (including IRQ - * setup and quirks) is complete before we enumerate I2C - * child devices. - */ - scoped_guard(device, gpio_dev) { - bound = device_is_bound(gpio_dev); - } - if (!bound) { - put_device(gpio_dev); - ret = -EPROBE_DEFER; - goto cleanup; - } - - put_device(gpio_dev); - } - -cleanup: - list_for_each_entry_safe(ref, tmp, &ctx.gpio_controllers, node) { - list_del(&ref->node); - kfree(ref->path); - kfree(ref); - } - - return ret; -} -#else -static int i2c_dw_check_gpio_dependencies(struct device *dev) -{ - return 0; -} -#endif /* CONFIG_ACPI */ - static int dw_i2c_plat_probe(struct platform_device *pdev) { u32 flags = (uintptr_t)device_get_match_data(&pdev->dev); @@ -286,14 +138,6 @@ static int dw_i2c_plat_probe(struct platform_device *pdev) struct dw_i2c_dev *dev; int irq, ret; - /* - * Check if any child devices have GpioInt resources, and if so, - * defer probe until those GPIO controllers are fully bound. - */ - ret = i2c_dw_check_gpio_dependencies(device); - if (ret) - return ret; - irq = platform_get_irq_optional(pdev, 0); if (irq == -ENXIO) flags |= ACCESS_POLLING; base-commit: 3f786abd23951f3f600a62fef42469d9200d5f52 prerequisite-patch-id: 22fa9ba20fa28cf94185281704c51feef7abc701 -- 2.54.0