Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754016AbbBEU4J (ORCPT ); Thu, 5 Feb 2015 15:56:09 -0500 Received: from mail-we0-f177.google.com ([74.125.82.177]:49673 "EHLO mail-we0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753021AbbBEU4H (ORCPT ); Thu, 5 Feb 2015 15:56:07 -0500 Message-ID: <1423169763.5723.47.camel@gmail.com> Subject: Re: [PATCH 2/2] clk: Fix OOPS calling hlist_del on an already poisoned hlist. From: Alban Browaeys To: Stephen Boyd Cc: Tomeu Vizoso , Mike Turquette , linux-kernel@vger.kernel.org Date: Thu, 05 Feb 2015 21:56:03 +0100 In-Reply-To: <54D3C587.9020309@codeaurora.org> References: <1423160690-7853-1-git-send-email-prahal@yahoo.com> <1423160690-7853-2-git-send-email-prahal@yahoo.com> <54D3C587.9020309@codeaurora.org> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.12.9-1+b1 Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7105 Lines: 101 Le jeudi 05 février 2015 à 11:33 -0800, Stephen Boyd a écrit : > On 02/05/15 10:24, Alban Browaeys wrote: > > Put is called more than once, thus hlist_del ends up on a poisoned > > list. > > Why is clk_put() called more than once on the same clk pointer? Where > does this happe > With only patch 1 from this set applied I get another oops: [ 7.346612] Unable to handle kernel paging request at virtual address 00200200 [ 7.353686] pgd = ebbf4000 [ 7.355939] [00200200] *pgd=00000000 [ 7.359444] Internal error: Oops: 805 [#1] PREEMPT SMP ARM [ 7.364914] Modules linked in: exynosdrm(+) drm_kms_helper phy_exynos_usb2 fuse [ 7.372201] CPU: 3 PID: 102 Comm: systemd-modules Not tainted 3.19.0-rc7-next-20150204-00053-g17e4521 #93 [ 7.381764] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) [ 7.387832] task: eb0a8f00 ti: ebbfe000 task.ti: ebbfe000 [ 7.393213] PC is at __clk_put+0x64/0xdc [ 7.397111] LR is at clk_prepare_lock+0x20/0x100 [ 7.401712] pc : [] lr : [] psr: 200f0053 [ 7.401712] sp : ebbffbb8 ip : ebbffba0 fp : ebbffbcc [ 7.413185] r10: ee0ff600 r9 : 00000001 r8 : 00000000 [ 7.413188] r7 : ebbffbf8 r6 : 00000000 r5 : ee5c7d80 r4 : ee0ff600 [ 7.413195] r3 : 00100100 r2 : 00200200 r1 : 080007ff r0 : 00000001 [ 7.413200] Flags: nzCv IRQs on FIQs off Mode SVC_32 ISA ARM Segment user [ 7.413204] Control: 10c5387d Table: 6bbf404a DAC: 00000015 [ 7.413208] Process systemd-modules (pid: 102, stack limit = 0xebbfe218) [ 7.413211] Stack: (0xebbffbb8 to 0xebc00000) [ 7.413215] fba0: 00000000 ee106400 [ 7.413222] fbc0: ebbffbdc ebbffbd0 c055222c c0556114 ebbffc6c ebbffbe0 c0558604 c0552220 [ 7.413228] fbe0: ebbffbf8 c01cc560 ebbbc310 ee2b5200 ebbffc14 c01ced00 ee5e0d3c 00000001 [ 7.413234] fc00: 00000181 ee2b5200 ebbffc34 ebbbc100 00000000 c08c5790 ee2b5200 ebbbc300 [ 7.413239] fc20: 00000001 00000006 ebbffc5c ebbffc38 c01ced00 c01cb2d0 ed834850 00000000 [ 7.413245] fc40: ed834858 ed834850 ed834850 bf06c0b4 c0aa82b8 00000000 bf06c0b4 00000006 [ 7.413251] fc60: ebbffc8c ebbffc70 c044213c c055846c ed834850 c0b61248 c0b61254 c0aa82b8 [ 7.413257] fc80: ebbffcc4 ebbffc90 c043ff34 c0442120 ed834850 bf06c0b4 ed834884 ed834850 [ 7.413263] fca0: bf06c0b4 ed834884 00000000 bf0631f0 eb3cfc00 c0a4f40c ebbffce4 ebbffcc8 [ 7.413269] fcc0: c044020c c043fdc8 00000000 00000000 bf06c0b4 c0440194 ebbffd0c ebbffce8 [ 7.413275] fce0: c043ded8 c04401a0 ee284e38 ed830900 c06f5720 bf06c0b4 eb329cc0 c0a87448 [ 7.413280] fd00: ebbffd1c ebbffd10 c043fa14 c043de88 ebbffd44 ebbffd20 c043f460 c043f9f4 [ 7.413286] fd20: bf069280 ebbffd30 bf06c0b4 00000000 bf0631e8 bf06c388 ebbffd5c ebbffd48 [ 7.413292] fd40: c0440bfc c043f370 00000001 00000000 ebbffd6c ebbffd60 c0442094 c0440b50 [ 7.413298] fd60: ebbffdbc ebbffd70 bf04ca08 c044203c 00000000 bf065090 ffffffff 00000000 [ 7.413303] fd80: 00000000 00000000 00000000 00000000 00000000 00000000 c0a53b20 bf06c208 [ 7.413309] fda0: c0a53b20 bf04c950 00000000 c0a53b20 ebbffe4c ebbffdc0 c0008b28 bf04c95c [ 7.413315] fdc0: 0010000f 00000000 ebbffdec ebbffdd8 c00504f4 c006dde0 ebbfe000 00000000 [ 7.413321] fde0: ee002140 000000d0 c06ed168 0000000c c0a50600 00000001 ebbffe4c ebbffe08 [ 7.413327] fe00: c01541d8 c0153934 ebbfe008 ebbffe08 00000001 ebbfe008 ee002140 dc8cb100 [ 7.413333] fe20: 00000001 bf06c208 00000001 eb3cfd00 eb3cf000 00000001 14c3101c eb3cf008 [ 7.413339] fe40: ebbffe74 ebbffe50 c06ed1a4 c00089ec ebbffe74 ebbffe60 c014496c ebbfff48 [ 7.413345] fe60: 00000001 bf06c208 ebbfff3c ebbffe78 c00af61c c06ed140 bf06c214 00007fff [ 7.413350] fe80: c00ac6a8 ebbfff48 ebbffeb4 f0473db8 00000780 00000777 f0473e84 bf06c214 [ 7.413356] fea0: bf06c378 b6dc99f8 bf06c250 c0a4f40c c00ad024 c0169924 00000000 00000000 [ 7.413362] fec0: bf063194 00000009 00000000 00000000 6e72656b 00006c65 00000000 00000000 [ 7.413367] fee0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 [ 7.413373] ff00: 00000000 00000000 00000000 dc8cb100 ebbfff2c 00000000 00000006 b6dc99f8 [ 7.413379] ff20: 0000017b c000fb64 ebbfe000 00000000 ebbfffa4 ebbfff40 c00afdec c00ada4c [ 7.413385] ff40: c0180738 00000000 f0454000 002bb414 f070ec6c f066643f f066dd80 00020390 [ 7.413390] ff60: 00026450 bf06c1f0 00000001 00000000 0000002f 00000030 0000001a 00000000 [ 7.413396] ff80: 00000008 00000000 00000000 b6dca7d4 00028948 e1c5e100 00000000 ebbfffa8 [ 7.413402] ffa0: c000f9c0 c00afd54 b6dca7d4 00028948 00000006 b6dc99f8 00000000 b6dca31c [ 7.413408] ffc0: b6dca7d4 00028948 e1c5e100 0000017b 00020000 00015964 00015f34 0002e640 [ 7.413414] ffe0: bedc0268 bedc0258 b6dc3c4b b6e6cd42 600d0070 00000006 6f7fd821 6f7fdc21 [ 7.413427] [] (__clk_put) from [] (clk_put+0x18/0x1c) [ 7.413438] [] (clk_put) from [] (of_clk_set_defaults+0x1a4/0x2ec) [ 7.413448] [] (of_clk_set_defaults) from [] (platform_drv_probe+0x28/0xb0) [ 7.413462] [] (platform_drv_probe) from [] (driver_probe_device+0x178/0x384) [ 7.413470] [] (driver_probe_device) from [] (__driver_attach+0x78/0x9c) [ 7.413478] [] (__driver_attach) from [] (bus_for_each_dev+0x5c/0xb4) [ 7.413485] [] (bus_for_each_dev) from [] (driver_attach+0x2c/0x30) [ 7.413492] [] (driver_attach) from [] (bus_add_driver+0xfc/0x228) [ 7.413500] [] (bus_add_driver) from [] (driver_register+0xb8/0xf8) [ 7.413509] [] (driver_register) from [] (__platform_driver_register+0x64/0x6c) [ 7.413597] [] (__platform_driver_register) from [] (exynos_drm_init+0xb8/0x1d0 [exynosdrm]) [ 7.413631] [] (exynos_drm_init [exynosdrm]) from [] (do_one_initcall+0x148/0x224) [ 7.413644] [] (do_one_initcall) from [] (do_init_module+0x70/0x1bc) [ 7.413657] [] (do_init_module) from [] (load_module+0x1bdc/0x21f0) [ 7.413665] [] (load_module) from [] (SyS_finit_module+0xa4/0xb4) [ 7.413675] [] (SyS_finit_module) from [] (ret_fast_syscall+0x0/0x34) [ 7.413681] Code: ebfff29e e5943014 e5942018 e3530000 (e582300 from the patch 1 debugging I concluded that in __set_clk_parents, the parent clk of the fimc devices was the same thus clk_put was called for each of the four of them (but oops at the second one). This indeed would deserve a debug run of itself. I only deduced the second oops behaviour from the analysis of the first oops as both happens in the same loop . This is weak. Will do the detailed testing for this one too . -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/