On Mon, 29 Aug 2016 18:36:47 +0530 Srikar Dronamraju <srikar@xxxxxxxxxxxxxxxxxx> wrote: > Fadump kernel reserves large chunks of memory even before the pages are > initialised. This could mean memory that corresponds to several nodes might > fall in memblock reserved regions. > > Kernels compiled with CONFIG_DEFERRED_STRUCT_PAGE_INIT will initialise > only certain size memory per node. The certain size takes into account > the dentry and inode cache sizes. However such a kernel when booting a > secondary kernel will not be able to allocate the required amount of > memory to suffice for the dentry and inode caches. This results in > crashes like the below on large systems such as 32 TB systems. > > Dentry cache hash table entries: 536870912 (order: 16, 4294967296 bytes) > vmalloc: allocation failure, allocated 4097114112 of 17179934720 bytes > swapper/0: page allocation failure: order:0, mode:0x2080020(GFP_ATOMIC) > CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6-master+ #3 > Call Trace: > [c00000000108fb10] [c0000000007fac88] dump_stack+0xb0/0xf0 (unreliable) > [c00000000108fb50] [c000000000235264] warn_alloc_failed+0x114/0x160 > [c00000000108fbf0] [c000000000281484] __vmalloc_node_range+0x304/0x340 > [c00000000108fca0] [c00000000028152c] __vmalloc+0x6c/0x90 > [c00000000108fd40] [c000000000aecfb0] > alloc_large_system_hash+0x1b8/0x2c0 > [c00000000108fe00] [c000000000af7240] inode_init+0x94/0xe4 > [c00000000108fe80] [c000000000af6fec] vfs_caches_init+0x8c/0x13c > [c00000000108ff00] [c000000000ac4014] start_kernel+0x50c/0x578 > [c00000000108ff90] [c000000000008c6c] start_here_common+0x20/0xa8 > > This patchset solves this problem by accounting the size of reserved memory > when calculating the size of large system hashes. What's the priority on this, btw? Not needed in earlier kernels? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>