509a80c49c
if CONFIG_PAGEALLOC is enabled then X86_FEATURE_PSE is disabled and all the kernel physical RAM pagetables are set up as 4K pages. This is needed so that CONFIG_PAGEALLOC can do finegrained mapping and unmapping of pages. as a side-effect though, the total size of memory allocated as kernel pagetables increases significantly. All these pagetables are allocated via alloc_bootmem_low_pages(), straight out of the lowmem DMA pool. If the system has enough RAM and a large kernel image then almost all of the 16 MB lowmem DMA pool is allocated to the image and to pagetables - leaving no space for __GFP_DMA allocations. this results in drivers failing and the bootup hanging: swapper invoked oom-killer: gfp_mask=0x80d1, order=0, oomkilladj=0 [<4015059f>] out_of_memory+0x17f/0x1c0 [<40151f3c>] __alloc_pages+0x37c/0x3a0 [<40168cd7>] slob_new_page+0x37/0x50 [<40168dff>] slob_alloc+0x10f/0x190 [<40169010>] __kmalloc_node+0x80/0x90 [<405a17e3>] scsi_host_alloc+0x33/0x2c0 [<405a1a82>] scsi_register+0x12/0x60 [<40d5889e>] aha1542_detect+0x9e/0x940 [<405c5ba5>] ultrastor_detect+0x265/0x5f0 [<401352f5>] getnstimeofday+0x35/0xf0 [<40d58751>] init_this_scsi_driver+0x41/0xf0 [<40d0b856>] kernel_init+0x136/0x310 [<40d58710>] init_this_scsi_driver+0x0/0xf0 [<40d0b720>] kernel_init+0x0/0x310 [<40105547>] kernel_thread_helper+0x7/0x10 ======================= the fix is to first allocate from above the DMA pool, and if that fails (for example due to it being a machine with less than 16 MB of RAM), allocate from the DMA pool as a fallback. With this fix applied i was able to boot a PAGEALLOC=y kernel that would hang before. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> |
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| .. | ||
| boot_ioremap_32.c | ||
| discontig_32.c | ||
| extable_32.c | ||
| extable_64.c | ||
| fault_32.c | ||
| fault_64.c | ||
| highmem_32.c | ||
| hugetlbpage.c | ||
| init_32.c | ||
| init_64.c | ||
| ioremap_32.c | ||
| ioremap_64.c | ||
| k8topology_64.c | ||
| Makefile | ||
| Makefile_32 | ||
| Makefile_64 | ||
| mmap_32.c | ||
| mmap_64.c | ||
| numa_64.c | ||
| pageattr_32.c | ||
| pageattr_64.c | ||
| pgtable_32.c | ||
| srat_64.c | ||