On Tue, Jul 30, 2019 at 04:22:37PM -0400, Qian Cai wrote: > On Tue, 2019-07-30 at 12:57 -0700, Andrew Morton wrote: > > On Sat, 27 Jul 2019 14:23:33 +0100 Catalin Marinas <catalin.marinas@xxxxxxx> > > > --- a/Documentation/admin-guide/kernel-parameters.txt > > > +++ b/Documentation/admin-guide/kernel-parameters.txt > > > @@ -2011,6 +2011,12 @@ > > > Built with CONFIG_DEBUG_KMEMLEAK_DEFAULT_OFF=y, > > > the default is off. > > > > > > + kmemleak.mempool= > > > + [KNL] Boot-time tuning of the minimum kmemleak > > > + metadata pool size. > > > + Format: <int> > > > + Default: NR_CPUS * 4 > > > + > > Catalin, BTW, it is right now unable to handle a large size. I tried to reserve > 64M (kmemleak.mempool=67108864), > > [ 0.039254][ T0] WARNING: CPU: 0 PID: 0 at mm/page_alloc.c:4707 __alloc_pages_nodemask+0x3b8/0x1780 [...] > [ 0.039646][ T0] NIP [c000000000395038] __alloc_pages_nodemask+0x3b8/0x1780 > [ 0.039693][ T0] LR [c0000000003d9320] kmalloc_large_node+0x100/0x1a0 > [ 0.039727][ T0] Call Trace: > [ 0.039795][ T0] [c00000000170fc80] [c0000000003e5080] __kmalloc_node+0x520/0x890 > [ 0.039816][ T0] [c00000000170fd20] [c0000000002e9544] mempool_init_node+0xb4/0x1e0 > [ 0.039836][ T0] [c00000000170fd80] [c0000000002e975c] mempool_create_node+0xcc/0x150 > [ 0.039857][ T0] [c00000000170fdf0] [c000000000b2a730] kmemleak_init+0x16c/0x54c > [ 0.039878][ T0] [c00000000170fef0] [c000000000ae460c] start_kernel+0x69c/0x7cc > [ 0.039908][ T0] [c00000000170ff90] [c00000000000a7d4] start_here_common+0x1c/0x434 [...] > [ 0.040100][ T0] kmemleak: Kernel memory leak detector disabled It looks like the mempool cannot be created. 64M objects means a kmalloc(512MB) for the pool array in mempool_init_node(), so that hits the MAX_ORDER warning in __alloc_pages_nodemask(). Maybe the mempool tunable won't help much for your case if you need so many objects. It's still worth having a mempool for kmemleak but we could look into changing the refill logic while keeping the original size constant (say 1024 objects). > [ 16.192449][ T1] BUG: Unable to handle kernel data access at 0xffffffffffffb2aa This doesn't seem kmemleak related from the trace. -- Catalin
