Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752475Ab1C2KkR (ORCPT ); Tue, 29 Mar 2011 06:40:17 -0400 Received: from service87.mimecast.com ([94.185.240.25]:43388 "HELO service87.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1751353Ab1C2KkP convert rfc822-to-8bit (ORCPT ); Tue, 29 Mar 2011 06:40:15 -0400 Subject: Re: kmemleak for MIPS From: Catalin Marinas To: Maxin John Cc: Daniel Baluta , naveen yadav , linux-mips@linux-mips.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org In-Reply-To: References: <9bde694e1003020554p7c8ff3c2o4ae7cb5d501d1ab9@mail.gmail.com> <1300960540.32158.13.camel@e102109-lin.cambridge.arm.com> Organization: ARM Limited Date: Tue, 29 Mar 2011 11:40:06 +0100 Message-ID: <1301395206.583.53.camel@e102109-lin.cambridge.arm.com> Mime-Version: 1.0 X-Mailer: Evolution 2.28.1 X-OriginalArrivalTime: 29 Mar 2011 10:40:07.0234 (UTC) FILETIME=[ABA3D220:01CBEDFD] X-MC-Unique: 111032911400908201 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3857 Lines: 97 On Mon, 2011-03-28 at 22:15 +0100, Maxin John wrote: > > Just add "depends on MIPS" and give it a try. > As per your suggestion, I have tried it in my qemu environment (MIPS malta). > > With a minor modification in arch/mips/kernel/vmlinux.lds.S (added the > symbol _sdata ), I was able to add kmemleak support for MIPS. > > Output in MIPS (Malta): You may want to disable the kmemleak testing to reduce the amount of leaks reported. > debian-mips:~# uname -a > Linux debian-mips 2.6.38-08826-g1788c20-dirty #4 SMP Mon Mar 28 > 23:22:04 EEST 2011 mips GNU/Linux > debian-mips:~# mount -t debugfs nodev /sys/kernel/debug/ > debian-mips:~# cat /sys/kernel/debug/kmemleak > unreferenced object 0x8f95d000 (size 4096): > comm "swapper", pid 1, jiffies 4294937330 (age 467.240s) > hex dump (first 32 bytes): > 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > backtrace: > [<80529644>] alloc_large_system_hash+0x2f8/0x410 > [<8053864c>] udp_table_init+0x4c/0x158 > [<80538774>] udp_init+0x1c/0x94 > [<80538b34>] inet_init+0x184/0x2a0 > [<80100584>] do_one_initcall+0x174/0x1e0 > [<8051f348>] kernel_init+0xe4/0x174 > [<80103d4c>] kernel_thread_helper+0x10/0x18 > unreferenced object 0x8f95e000 (size 4096): > comm "swapper", pid 1, jiffies 4294937330 (age 467.240s) > hex dump (first 32 bytes): > 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > backtrace: > [<80529644>] alloc_large_system_hash+0x2f8/0x410 > [<8053864c>] udp_table_init+0x4c/0x158 > [<8053881c>] udplite4_register+0x24/0xa8 > [<80538b3c>] inet_init+0x18c/0x2a0 > [<80100584>] do_one_initcall+0x174/0x1e0 > [<8051f348>] kernel_init+0xe4/0x174 > [<80103d4c>] kernel_thread_helper+0x10/0x18 These are probably false positives. Since the pointer referring this block (udp_table) is __read_mostly, is it possible that the corresponding section gets placed outside the _sdata.._edata range? diff --git a/arch/mips/include/asm/cache.h b/arch/mips/include/asm/cache.h index 650ac9b..b4db69f 100644 --- a/arch/mips/include/asm/cache.h +++ b/arch/mips/include/asm/cache.h @@ -17,6 +17,6 @@ #define SMP_CACHE_SHIFT L1_CACHE_SHIFT #define SMP_CACHE_BYTES L1_CACHE_BYTES -#define __read_mostly __attribute__((__section__(".data.read_mostly"))) +#define __read_mostly __attribute__((__section__(".data..read_mostly"))) #endif /* _ASM_CACHE_H */ diff --git a/arch/mips/kernel/vmlinux.lds.S b/arch/mips/kernel/vmlinux.lds.S index 570607b..6f6d5d0 100644 --- a/arch/mips/kernel/vmlinux.lds.S +++ b/arch/mips/kernel/vmlinux.lds.S @@ -74,6 +74,7 @@ SECTIONS INIT_TASK_DATA(PAGE_SIZE) NOSAVE_DATA CACHELINE_ALIGNED_DATA(1 << CONFIG_MIPS_L1_CACHE_SHIFT) + READ_MOSTLY_DATA(1 << CONFIG_MIPS_L1_CACHE_SHIFT) DATA_DATA CONSTRUCTORS } > unreferenced object 0x8f072000 (size 4096): > comm "swapper", pid 1, jiffies 4294937680 (age 463.840s) > hex dump (first 32 bytes): > 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > backtrace: > [<801ba3d8>] __kmalloc+0x130/0x180 > [<805461bc>] flow_cache_cpu_prepare+0x50/0xa8 > [<8053746c>] flow_cache_init_global+0x90/0x138 > [<80100584>] do_one_initcall+0x174/0x1e0 > [<8051f348>] kernel_init+0xe4/0x174 > [<80103d4c>] kernel_thread_helper+0x10/0x18 Same here, flow_cachep pointer is __read_mostly. -- Catalin -- 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/