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 3D56FC47DD9 for ; Fri, 22 Mar 2024 17:01:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=oFU02zMk5rSXKNtzpgigglLp5ddGCUhc6VsKgBP54oY=; b=nh4VCuL1LnvbNt 2/7hKLPbKG5AvjzVW8Npm5u9+s+OehatD+wAnCuTjCuzouM+L830EaXeBZNhESAF5y22JmsTsknBW oXHzGISZzHIHwjl1CNL08j/BFpONRhvJo+h+RGcqk6Rzskdci4hOeWLLvSCe3vZRduvJqDq59AdZr IZxzODrLM0GnFwz20VbR5enXXmzjFxxjLamShVSS4z9vK0KVu5lQTFmYoSs+UFH+0ZhCOMF6kUl+o N7xNoajo4I6yk+l//l8jg0bXHjZJLCQ3/oSDBKY+kjaotuSO185cQLyFS9wDWZ6sm4fyw44vvGjLl pD73C9c7m5wtiKNorECg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rniGF-0000000844q-1JTi; Fri, 22 Mar 2024 17:00:55 +0000 Received: from sin.source.kernel.org ([145.40.73.55]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rniGB-0000000843n-4BKv for linux-arm-kernel@lists.infradead.org; Fri, 22 Mar 2024 17:00:53 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sin.source.kernel.org (Postfix) with ESMTP id AEEA9CE10AC; Fri, 22 Mar 2024 17:00:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 81A9CC433C7; Fri, 22 Mar 2024 17:00:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1711126848; bh=CuEL8DTKaHcVBhcZt4WzvXtU5ff2h1A3Pqle55mHAOk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=G6hF0qZmvPOdqDBKWJbPvCD8CZS2SLVCBA4nhYyv7dFG5ueIARi/Pa93/GPzBeUZb Z/Bh/gBAZULimKRn9bnI2oXHazHeeCDHVFmcPRN0830LtiXHsIf4Plw21SOLXR6HOi vWUSWIQA0Jhppb1o5lQfdj9R5XsaZ28m75Wf2qkXWSxL5i1uAL9pINT51poibnOrjZ oQUrrMjbf1gEJPWDBlsTLAoXH+hFbJY+dZLq2RIuPfinGt6Dxnev28O0bc+mBLlpWF mGc4VDApLFnGpcj/WBj36jIGlCqdNx3Vn9X+Sp355BgIvknsPLvROM5GK9nVPZ1+rI 24jEB92m+iGfg== Received: from johan by xi.lan with local (Exim 4.97.1) (envelope-from ) id 1rniGI-000000006Kx-1Z57; Fri, 22 Mar 2024 18:00:58 +0100 Date: Fri, 22 Mar 2024 18:00:58 +0100 From: Johan Hovold To: Bjorn Andersson Cc: Bjorn Andersson , Konrad Dybcio , Michael Turquette , Stephen Boyd , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Taniya Das , Johan Hovold , linux-arm-msm@vger.kernel.org, linux-clk@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Ulf Hansson , Rob Clark , Abhinav Kumar , Dmitry Baryshkov Subject: Re: [PATCH v4 2/8] clk: qcom: gdsc: Enable supply reglator in GPU GX handler Message-ID: References: <20240125-sa8295p-gpu-v4-0-7011c2a63037@quicinc.com> <20240125-sa8295p-gpu-v4-2-7011c2a63037@quicinc.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20240125-sa8295p-gpu-v4-2-7011c2a63037@quicinc.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240322_100052_494591_F0E6ED81 X-CRM114-Status: GOOD ( 23.83 ) 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: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, Jan 25, 2024 at 01:05:08PM -0800, Bjorn Andersson wrote: > The GX GDSC is modelled to aid the GMU in powering down the GPU in the > event that the GPU crashes, so that it can be restarted again. But in > the event that the power-domain is supplied through a dedicated > regulator (in contrast to being a subdomin of another power-domain), > something needs to turn that regulator on, both to make sure things are > powered and to match the operation in gdsc_disable(). > > Reviewed-by: Konrad Dybcio > Signed-off-by: Bjorn Andersson > --- > drivers/clk/qcom/gdsc.c | 12 ++++++++++-- > 1 file changed, 10 insertions(+), 2 deletions(-) > > diff --git a/drivers/clk/qcom/gdsc.c b/drivers/clk/qcom/gdsc.c > index 5358e28122ab..e7a4068b9f39 100644 > --- a/drivers/clk/qcom/gdsc.c > +++ b/drivers/clk/qcom/gdsc.c > @@ -557,7 +557,15 @@ void gdsc_unregister(struct gdsc_desc *desc) > */ > int gdsc_gx_do_nothing_enable(struct generic_pm_domain *domain) > { > - /* Do nothing but give genpd the impression that we were successful */ > - return 0; > + struct gdsc *sc = domain_to_gdsc(domain); > + int ret = 0; > + > + /* Enable the parent supply, when controlled through the regulator framework. */ > + if (sc->rsupply) > + ret = regulator_enable(sc->rsupply); > + > + /* Do nothing with the GDSC itself */ > + > + return ret; > } > EXPORT_SYMBOL_GPL(gdsc_gx_do_nothing_enable); This patch (and series) is now in mainline as commit 9187ebb954ab ("clk: qcom: gdsc: Enable supply reglator in GPU GX handler") and appears to be involved in triggering the below lockdep splat on boot of the Lenovo ThinkPad X13s. Adding Ulf and the MSM DRM devs as well in case I blamed the wrong change here. Johan [ 5.849106] ====================================================== [ 5.849111] WARNING: possible circular locking dependency detected [ 5.849115] 6.8.0 #111 Not tainted [ 5.849119] ------------------------------------------------------ [ 5.849123] kworker/u32:2/66 is trying to acquire lock: [ 5.849128] ffffaffb0ca9b4f0 (regulator_list_mutex){+.+.}-{3:3}, at: regulator_lock_dependent+0x54/0x27c [ 5.849148] but task is already holding lock: [ 5.849152] ffffaffad8f33a00 (&genpd->mlock){+.+.}-{3:3}, at: genpd_lock_mtx+0x18/0x24 [ 5.849165] which lock already depends on the new lock. [ 5.849170] the existing dependency chain (in reverse order) is: [ 5.849175] -> #3 (&genpd->mlock){+.+.}-{3:3}: [ 5.849182] lock_acquire+0x68/0x84 [ 5.849190] __mutex_lock+0xa0/0x840 [ 5.849197] mutex_lock_nested+0x24/0x30 [ 5.849201] genpd_lock_mtx+0x18/0x24 [ 5.849206] genpd_runtime_resume+0x104/0x2f4 [ 5.849211] __rpm_callback+0x48/0x1a8 [ 5.849218] rpm_callback+0x68/0x74 [ 5.849223] rpm_resume+0x444/0x638 [ 5.849228] __pm_runtime_resume+0x5c/0xbc [ 5.849233] device_link_add+0x680/0x6e8 [ 5.849239] arm_smmu_probe_device+0x2a4/0x3e4 [ 5.849245] __iommu_probe_device+0x108/0x430 [ 5.849250] iommu_probe_device+0x3c/0x80 [ 5.849255] of_iommu_configure+0x170/0x25c [ 5.849260] of_dma_configure_id+0x10c/0x340 [ 5.849265] platform_dma_configure+0x78/0xbc [ 5.849270] really_probe+0x74/0x388 [ 5.849276] __driver_probe_device+0x7c/0x160 [ 5.849281] driver_probe_device+0x40/0x114 [ 5.849287] __driver_attach+0xfc/0x208 [ 5.849292] bus_for_each_dev+0x74/0xd0 [ 5.849296] driver_attach+0x24/0x30 [ 5.849301] bus_add_driver+0x110/0x214 [ 5.849306] driver_register+0x60/0x128 [ 5.849312] __platform_driver_register+0x28/0x34 [ 5.849316] panel_edp_init+0x20/0x1000 [panel_edp] [ 5.849329] panel_edp_init+0xc8/0x1000 [panel_edp] [ 5.849337] do_one_initcall+0x74/0x344 [ 5.849342] do_init_module+0x5c/0x1f8 [ 5.849347] load_module+0x1c9c/0x1e18 [ 5.849351] init_module_from_file+0x84/0xc0 [ 5.849356] idempotent_init_module+0x180/0x250 [ 5.849360] __arm64_sys_finit_module+0x68/0xcc [ 5.849365] invoke_syscall+0x48/0x114 [ 5.849370] el0_svc_common.constprop.0+0xc0/0xe0 [ 5.849376] do_el0_svc+0x1c/0x28 [ 5.849381] el0_svc+0x48/0x114 [ 5.849386] el0t_64_sync_handler+0xc0/0xc4 [ 5.849391] el0t_64_sync+0x190/0x194 [ 5.849395] -> #2 (dpm_list_mtx){+.+.}-{3:3}: [ 5.849403] lock_acquire+0x68/0x84 [ 5.849408] __mutex_lock+0xa0/0x840 [ 5.849412] mutex_lock_nested+0x24/0x30 [ 5.849416] device_pm_lock+0x1c/0x28 [ 5.849422] device_link_add+0x274/0x6e8 [ 5.849426] fw_devlink_create_devlink+0x118/0x2fc [ 5.849431] __fw_devlink_link_to_consumers.isra.0+0x50/0x104 [ 5.849437] device_add+0x744/0x7b0 [ 5.849441] of_device_add+0x44/0x60 [ 5.849446] of_platform_device_create_pdata+0x98/0x140 [ 5.849451] of_platform_bus_create+0x1b4/0x4b4 [ 5.849455] of_platform_populate+0x58/0x150 [ 5.849459] of_platform_default_populate_init+0xd8/0xf0 [ 5.849466] do_one_initcall+0x74/0x344 [ 5.849470] kernel_init_freeable+0x244/0x350 [ 5.849476] kernel_init+0x20/0x1d8 [ 5.849480] ret_from_fork+0x10/0x20 [ 5.849484] -> #1 (device_links_lock){+.+.}-{3:3}: [ 5.849492] lock_acquire+0x68/0x84 [ 5.849497] __mutex_lock+0xa0/0x840 [ 5.849501] mutex_lock_nested+0x24/0x30 [ 5.849505] device_link_remove+0x38/0x94 [ 5.849509] _regulator_put.part.0+0x168/0x190 [ 5.849515] regulator_bulk_free+0x64/0x90 [ 5.849521] devm_regulator_bulk_release+0x1c/0x28 [ 5.849526] release_nodes+0x5c/0x90 [ 5.849532] devres_release_group+0xc8/0x134 [ 5.849537] i2c_device_probe+0x138/0x2e8 [i2c_core] [ 5.849549] really_probe+0xc0/0x388 [ 5.849554] __driver_probe_device+0x7c/0x160 [ 5.849559] driver_probe_device+0x40/0x114 [ 5.849565] __device_attach_driver+0xbc/0x158 [ 5.849571] bus_for_each_drv+0x84/0xe0 [ 5.849576] __device_attach_async_helper+0xb0/0x10c [ 5.849582] async_run_entry_fn+0x34/0x14c [ 5.849588] process_one_work+0x220/0x634 [ 5.849595] worker_thread+0x268/0x3a8 [ 5.849599] kthread+0x124/0x128 [ 5.849603] ret_from_fork+0x10/0x20 [ 5.849608] -> #0 (regulator_list_mutex){+.+.}-{3:3}: [ 5.849615] __lock_acquire+0x130c/0x2064 [ 5.849621] lock_acquire.part.0+0xc8/0x20c [ 5.849626] lock_acquire+0x68/0x84 [ 5.849631] __mutex_lock+0xa0/0x840 [ 5.849636] mutex_lock_nested+0x24/0x30 [ 5.849640] regulator_lock_dependent+0x54/0x27c [ 5.849646] regulator_enable+0x34/0xd0 [ 5.849651] gdsc_gx_do_nothing_enable+0x18/0x2c [ 5.849659] _genpd_power_on+0x94/0x17c [ 5.849664] genpd_power_on.part.0+0xa4/0x1a8 [ 5.849669] genpd_runtime_resume+0x120/0x2f4 [ 5.849673] __rpm_callback+0x48/0x1a8 [ 5.849678] rpm_callback+0x68/0x74 [ 5.849683] rpm_resume+0x584/0x638 [ 5.849688] __pm_runtime_resume+0x5c/0xbc [ 5.849693] a6xx_gmu_resume+0x70/0xcf8 [msm] [ 5.849722] a6xx_gmu_pm_resume+0x3c/0x284 [msm] [ 5.849745] adreno_runtime_resume+0x28/0x34 [msm] [ 5.849769] pm_generic_runtime_resume+0x2c/0x44 [ 5.849774] __rpm_callback+0x48/0x1a8 [ 5.849779] rpm_callback+0x68/0x74 [ 5.849783] rpm_resume+0x444/0x638 [ 5.849788] __pm_runtime_resume+0x5c/0xbc [ 5.849793] adreno_load_gpu+0x78/0x238 [msm] [ 5.849816] msm_open+0x114/0x128 [msm] [ 5.849843] drm_file_alloc+0x184/0x2a8 [drm] [ 5.849876] drm_client_init+0x7c/0x10c [drm] [ 5.849900] msm_fbdev_setup+0x84/0x150 [msm] [ 5.849929] msm_drm_bind+0x264/0x420 [msm] [ 5.849950] try_to_bring_up_aggregate_device+0x1ec/0x2f4 [ 5.849962] __component_add+0xa8/0x194 [ 5.849965] component_add+0x14/0x20 [ 5.849967] dp_display_probe_tail+0x4c/0xac [msm] [ 5.850000] dp_auxbus_done_probe+0x14/0x20 [msm] [ 5.850023] dp_aux_ep_probe+0x4c/0xf0 [drm_dp_aux_bus] [ 5.850030] really_probe+0xc0/0x388 [ 5.850034] __driver_probe_device+0x7c/0x160 [ 5.850038] driver_probe_device+0x40/0x114 [ 5.850042] __device_attach_driver+0xbc/0x158 [ 5.850046] bus_for_each_drv+0x84/0xe0 [ 5.850050] __device_attach+0xa8/0x1d4 [ 5.850053] device_initial_probe+0x14/0x20 [ 5.850058] bus_probe_device+0xb0/0xb4 [ 5.850061] device_add+0x5b8/0x7b0 [ 5.850065] device_register+0x20/0x30 [ 5.850068] of_dp_aux_populate_bus+0xcc/0x1a0 [drm_dp_aux_bus] [ 5.850074] devm_of_dp_aux_populate_bus+0x18/0x80 [drm_dp_aux_bus] [ 5.850080] dp_display_probe+0x2a4/0x454 [msm] [ 5.850098] platform_probe+0x68/0xd8 [ 5.850102] really_probe+0xc0/0x388 [ 5.850106] __driver_probe_device+0x7c/0x160 [ 5.850109] driver_probe_device+0x40/0x114 [ 5.850113] __device_attach_driver+0xbc/0x158 [ 5.850117] bus_for_each_drv+0x84/0xe0 [ 5.850121] __device_attach+0xa8/0x1d4 [ 5.850125] device_initial_probe+0x14/0x20 [ 5.850129] bus_probe_device+0xb0/0xb4 [ 5.850133] deferred_probe_work_func+0xa0/0xf4 [ 5.850137] process_one_work+0x220/0x634 [ 5.850141] worker_thread+0x268/0x3a8 [ 5.850144] kthread+0x124/0x128 [ 5.850147] ret_from_fork+0x10/0x20 [ 5.850151] other info that might help us debug this: [ 5.850154] Chain exists of: regulator_list_mutex --> dpm_list_mtx --> &genpd->mlock [ 5.850163] Possible unsafe locking scenario: [ 5.850166] CPU0 CPU1 [ 5.850168] ---- ---- [ 5.850171] lock(&genpd->mlock); [ 5.850174] lock(dpm_list_mtx); [ 5.850178] lock(&genpd->mlock); [ 5.850182] lock(regulator_list_mutex); [ 5.850185] *** DEADLOCK *** [ 5.850188] 8 locks held by kworker/u32:2/66: [ 5.850191] #0: ffff2be180020948 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1a0/0x634 [ 5.850199] #1: ffff800081033de0 (deferred_probe_work){+.+.}-{0:0}, at: process_one_work+0x1c8/0x634 [ 5.850207] #2: ffff2be1849e38f8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x38/0x1d4 [ 5.850215] #3: ffff2be183c550e8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x38/0x1d4 [ 5.850223] #4: ffffaffb0caa59e8 (component_mutex){+.+.}-{3:3}, at: __component_add+0x60/0x194 [ 5.850231] #5: ffffaffad96ee178 (init_lock){+.+.}-{3:3}, at: msm_open+0x38/0x128 [msm] [ 5.850252] #6: ffff2be18d6536d8 (&a6xx_gpu->gmu.lock){+.+.}-{3:3}, at: a6xx_gmu_pm_resume+0x34/0x284 [msm] [ 5.850274] #7: ffffaffad8f33a00 (&genpd->mlock){+.+.}-{3:3}, at: genpd_lock_mtx+0x18/0x24 [ 5.850282] stack backtrace: [ 5.850286] CPU: 6 PID: 66 Comm: kworker/u32:2 Not tainted 6.8.0 #111 [ 5.850291] Hardware name: LENOVO 21BYZ9SRUS/21BYZ9SRUS, BIOS N3HET87W (1.59 ) 12/05/2023 [ 5.850296] Workqueue: events_unbound deferred_probe_work_func [ 5.850301] Call trace: [ 5.850303] dump_backtrace+0x9c/0x11c [ 5.850307] show_stack+0x18/0x24 [ 5.850312] dump_stack_lvl+0x90/0xd0 [ 5.850316] dump_stack+0x18/0x24 [ 5.850320] print_circular_bug+0x290/0x370 [ 5.850324] check_noncircular+0x15c/0x170 [ 5.850327] __lock_acquire+0x130c/0x2064 [ 5.850331] lock_acquire.part.0+0xc8/0x20c [ 5.850335] lock_acquire+0x68/0x84 [ 5.850339] __mutex_lock+0xa0/0x840 [ 5.850342] mutex_lock_nested+0x24/0x30 [ 5.850345] regulator_lock_dependent+0x54/0x27c [ 5.850349] regulator_enable+0x34/0xd0 [ 5.850352] gdsc_gx_do_nothing_enable+0x18/0x2c [ 5.850356] _genpd_power_on+0x94/0x17c [ 5.850360] genpd_power_on.part.0+0xa4/0x1a8 [ 5.850363] genpd_runtime_resume+0x120/0x2f4 [ 5.850366] __rpm_callback+0x48/0x1a8 [ 5.850370] rpm_callback+0x68/0x74 [ 5.850374] rpm_resume+0x584/0x638 [ 5.850377] __pm_runtime_resume+0x5c/0xbc [ 5.850381] a6xx_gmu_resume+0x70/0xcf8 [msm] [ 5.850398] a6xx_gmu_pm_resume+0x3c/0x284 [msm] [ 5.850416] adreno_runtime_resume+0x28/0x34 [msm] [ 5.850433] pm_generic_runtime_resume+0x2c/0x44 [ 5.850437] __rpm_callback+0x48/0x1a8 [ 5.850440] rpm_callback+0x68/0x74 [ 5.850443] rpm_resume+0x444/0x638 [ 5.850447] __pm_runtime_resume+0x5c/0xbc [ 5.850450] adreno_load_gpu+0x78/0x238 [msm] [ 5.850467] msm_open+0x114/0x128 [msm] [ 5.850485] drm_file_alloc+0x184/0x2a8 [drm] [ 5.850504] drm_client_init+0x7c/0x10c [drm] [ 5.850522] msm_fbdev_setup+0x84/0x150 [msm] [ 5.850540] msm_drm_bind+0x264/0x420 [msm] [ 5.850557] try_to_bring_up_aggregate_device+0x1ec/0x2f4 [ 5.850562] __component_add+0xa8/0x194 [ 5.850566] component_add+0x14/0x20 [ 5.850570] dp_display_probe_tail+0x4c/0xac [msm] [ 5.850587] dp_auxbus_done_probe+0x14/0x20 [msm] [ 5.850605] dp_aux_ep_probe+0x4c/0xf0 [drm_dp_aux_bus] [ 5.850611] really_probe+0xc0/0x388 [ 5.850615] __driver_probe_device+0x7c/0x160 [ 5.850619] driver_probe_device+0x40/0x114 [ 5.850624] __device_attach_driver+0xbc/0x158 [ 5.850628] bus_for_each_drv+0x84/0xe0 [ 5.850631] __device_attach+0xa8/0x1d4 [ 5.850635] device_initial_probe+0x14/0x20 [ 5.850639] bus_probe_device+0xb0/0xb4 [ 5.850642] device_add+0x5b8/0x7b0 [ 5.850645] device_register+0x20/0x30 [ 5.850648] of_dp_aux_populate_bus+0xcc/0x1a0 [drm_dp_aux_bus] [ 5.850654] devm_of_dp_aux_populate_bus+0x18/0x80 [drm_dp_aux_bus] [ 5.850660] dp_display_probe+0x2a4/0x454 [msm] [ 5.850678] platform_probe+0x68/0xd8 [ 5.850681] really_probe+0xc0/0x388 [ 5.850684] __driver_probe_device+0x7c/0x160 [ 5.850688] driver_probe_device+0x40/0x114 [ 5.850692] __device_attach_driver+0xbc/0x158 [ 5.850696] bus_for_each_drv+0x84/0xe0 [ 5.850699] __device_attach+0xa8/0x1d4 [ 5.850703] device_initial_probe+0x14/0x20 [ 5.850707] bus_probe_device+0xb0/0xb4 [ 5.850710] deferred_probe_work_func+0xa0/0xf4 [ 5.850714] process_one_work+0x220/0x634 [ 5.850717] worker_thread+0x268/0x3a8 [ 5.850720] kthread+0x124/0x128 [ 5.850723] ret_from_fork+0x10/0x20 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel