| Message ID | 20110926165024.GA21617@e102109-lin.cambridge.arm.com |
|---|---|
| State | Not Applicable, archived |
| Delegated to: | David Miller |
| Headers | show |
2011/9/27 Catalin Marinas <Catalin.Marinas@arm.com>: > On Mon, Sep 26, 2011 at 05:32:54PM +0100, Eric Dumazet wrote: >> Le lundi 26 septembre 2011 à 23:17 +0800, Huajun Li a écrit : >> > Memory leak detector gives following memory leak report, it seems the >> > report is triggered by net/core/flow.c, but actually, it should be a >> > false positive report. >> > So, is there any idea from kmemleak side to fix/disable this false >> > positive report like this? >> > Yes, kmemleak_not_leak(...) could disable it, but is it suitable for this case ? > ... >> CC lkml and percpu maintainers (Tejun Heo & Christoph Lameter ) as well >> >> AFAIK this false positive only occurs if percpu data is allocated >> outside of embedded pcu space. >> >> (grep pcpu_get_vm_areas /proc/vmallocinfo) >> >> I suspect this is a percpu/kmemleak cooperation problem (a missing >> kmemleak_alloc() ?) >> >> I am pretty sure kmemleak_not_leak() is not the right answer to this >> problem. > > kmemleak_not_leak() definitely not the write answer. The alloc_percpu() > call does not have any kmemleak_alloc() callback, so it doesn't scan > them. > > Huajun, could you please try the patch below: > > 8<-------------------------------- > kmemleak: Handle percpu memory allocation > > From: Catalin Marinas <catalin.marinas@arm.com> > > This patch adds kmemleak callbacks from the percpu allocator, reducing a > number of false positives caused by kmemleak not scanning such memory > blocks. > > Reported-by: Huajun Li <huajun.li.lee@gmail.com> > Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> > --- > mm/percpu.c | 11 +++++++++-- > 1 files changed, 9 insertions(+), 2 deletions(-) > > diff --git a/mm/percpu.c b/mm/percpu.c > index bf80e55..c47a90b 100644 > --- a/mm/percpu.c > +++ b/mm/percpu.c > @@ -67,6 +67,7 @@ > #include <linux/spinlock.h> > #include <linux/vmalloc.h> > #include <linux/workqueue.h> > +#include <linux/kmemleak.h> > > #include <asm/cacheflush.h> > #include <asm/sections.h> > @@ -833,7 +834,9 @@ fail_unlock_mutex: > */ > void __percpu *__alloc_percpu(size_t size, size_t align) > { > - return pcpu_alloc(size, align, false); > + void __percpu *ptr = pcpu_alloc(size, align, false); > + kmemleak_alloc(ptr, size, 1, GFP_KERNEL); > + return ptr; > } > EXPORT_SYMBOL_GPL(__alloc_percpu); > > @@ -855,7 +858,9 @@ EXPORT_SYMBOL_GPL(__alloc_percpu); > */ > void __percpu *__alloc_reserved_percpu(size_t size, size_t align) > { > - return pcpu_alloc(size, align, true); > + void __percpu *ptr = pcpu_alloc(size, align, true); > + kmemleak_alloc(ptr, size, 1, GFP_KERNEL); > + return ptr; > } > > /** > @@ -915,6 +920,8 @@ void free_percpu(void __percpu *ptr) > if (!ptr) > return; > > + kmemleak_free(ptr); > + > addr = __pcpu_ptr_to_addr(ptr); > > spin_lock_irqsave(&pcpu_lock, flags); > > -- > Catalin > Applied the patch and found following msg after system boot up : -------------------------------------------------------------------------------------------------------- ... [ 48.040027] eth0: no IPv6 routers present [ 69.240960] BUG: unable to handle kernel paging request at 00000000001d7270 [ 69.241010] IP: [<ffffffff81256c62>] scan_block+0x62/0x220 [ 69.241045] PGD 5f289067 PUD 5f292067 PMD 0 [ 69.241074] Oops: 0000 [#1] SMP [ 69.241098] CPU 0 [ 69.241110] Modules linked in: binfmt_misc dm_crypt snd_hda_codec_analog snd_hda_intel snd_hda_codec usbhid hid snd_hwdep snd_pcm snd_seq_midi snd_rawmidi i915 snd_seq_midi_event hp_wmi ppdev sparse_keymap snd_seq snd_timer snd_seq_device ehci_hcd uhci_hcd drm_kms_helper usbcore tpm_infineon psmouse snd e1000e drm serio_raw soundcore tpm_tis snd_page_alloc tpm floppy tpm_bios parport_pc i2c_algo_bit video lp parport [ 69.249303] [ 69.250246] Pid: 47, comm: kmemleak Tainted: G I 3.1.0-rc7+ #24 Hewlett-Packard HP Compaq dc7800p Convertible Minitower/0AACh [ 69.250246] RIP: 0010:[<ffffffff81256c62>] [<ffffffff81256c62>] scan_block+0x62/0x220 [ 69.250246] RSP: 0018:ffff880073f69d90 EFLAGS: 00010012 [ 69.250246] RAX: 0000000000000000 RBX: ffff880078750858 RCX: 0000000000000000 [ 69.250246] RDX: ffff880078750858 RSI: 0000000000000001 RDI: 00000000001d7270 [ 69.250246] RBP: ffff880073f69dd0 R08: 0000000000000000 R09: 0000000000000000 [ 69.250246] R10: 0000000000000001 R11: 0000000000000000 R12: ffff8800787508b8 [ 69.250246] R13: 00000000001d7270 R14: 00000000001d7431 R15: 0000000000000000 [ 69.250246] FS: 0000000000000000(0000) GS:ffff88007a200000(0000) knlGS:0000000000000000 [ 69.250246] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ 69.250246] CR2: 00000000001d7270 CR3: 000000006d735000 CR4: 00000000000006f0 [ 69.250246] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 69.250246] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 [ 69.250246] Process kmemleak (pid: 47, threadinfo ffff880073f68000, task ffff880073e4a460) [ 69.250246] Stack: [ 69.250246] ffff880073f69dd0 ffffffff8194b49a ffffffff81256ed1 ffff880078750858 [ 69.250246] ffff8800787508b8 00000000001d8270 00000000001d7438 0000000000000206 [ 69.250246] ffff880073f69e10 ffffffff8125702a 000000000007d2af ffffffff81e0d120 [ 69.250246] Call Trace: [ 69.250246] [<ffffffff8194b49a>] ? _raw_spin_lock_irqsave+0xfa/0x110 [ 69.250246] [<ffffffff81256ed1>] ? scan_gray_list+0xb1/0x280 [ 69.250246] [<ffffffff8125702a>] scan_gray_list+0x20a/0x280 [ 69.250246] [<ffffffff8125787a>] kmemleak_scan+0x44a/0xbd0 [ 69.250246] [<ffffffff81257430>] ? kmemleak_do_cleanup+0x210/0x210 [ 69.250246] [<ffffffff81258630>] ? kmemleak_write+0x630/0x630 [ 69.250246] [<ffffffff812586bf>] kmemleak_scan_thread+0x8f/0x150 [ 69.250246] [<ffffffff810dc4e6>] kthread+0xe6/0x100 [ 69.250246] [<ffffffff8195a4c4>] kernel_thread_helper+0x4/0x10 [ 69.250246] [<ffffffff8194ac50>] ? _raw_spin_unlock_irq+0x50/0x80 [ 69.250246] [<ffffffff8194b874>] ? retint_restore_args+0x13/0x13 [ 69.250246] [<ffffffff810dc400>] ? __init_kthread_worker+0x80/0x80 [ 69.250246] [<ffffffff8195a4c0>] ? gs_change+0x13/0x13 [ 69.250246] Code: 00 00 e9 d2 01 00 00 66 90 e8 ab f4 ff ff 48 83 05 33 ef 06 02 01 85 c0 0f 85 bb 01 00 00 48 83 05 2b ef 06 02 01 be 01 00 00 00 [ 69.250246] 8b 7d 00 e8 c5 fc ff ff 48 85 c0 49 89 c4 0f 84 69 01 00 00 [ 69.250246] RIP [<ffffffff81256c62>] scan_block+0x62/0x220 [ 69.250246] RSP <ffff880073f69d90> [ 69.250246] CR2: 00000000001d7270 [ 69.360917] ---[ end trace a7919e7f17c0a727 ]--- -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/mm/percpu.c b/mm/percpu.c index bf80e55..c47a90b 100644 --- a/mm/percpu.c +++ b/mm/percpu.c @@ -67,6 +67,7 @@ #include <linux/spinlock.h> #include <linux/vmalloc.h> #include <linux/workqueue.h> +#include <linux/kmemleak.h> #include <asm/cacheflush.h> #include <asm/sections.h> @@ -833,7 +834,9 @@ fail_unlock_mutex: */ void __percpu *__alloc_percpu(size_t size, size_t align) { - return pcpu_alloc(size, align, false); + void __percpu *ptr = pcpu_alloc(size, align, false); + kmemleak_alloc(ptr, size, 1, GFP_KERNEL); + return ptr; } EXPORT_SYMBOL_GPL(__alloc_percpu); @@ -855,7 +858,9 @@ EXPORT_SYMBOL_GPL(__alloc_percpu); */ void __percpu *__alloc_reserved_percpu(size_t size, size_t align) { - return pcpu_alloc(size, align, true); + void __percpu *ptr = pcpu_alloc(size, align, true); + kmemleak_alloc(ptr, size, 1, GFP_KERNEL); + return ptr; } /** @@ -915,6 +920,8 @@ void free_percpu(void __percpu *ptr) if (!ptr) return; + kmemleak_free(ptr); + addr = __pcpu_ptr_to_addr(ptr); spin_lock_irqsave(&pcpu_lock, flags);