On Thu, Apr 16, 2015 at 06:57:46PM +0200, Dorian Gray wrote: > On 16 April 2015 at 16:15, Alan Stern <st...@rowland.harvard.edu> wrote: > > This appears to be a problem with the IOMMU or SWIOTLB subsystems, not > > the USB subsystem. I have CC'ed the appropriate mailing lists. > > Thanks, I'm far from being a kernel expert, so was expecting it could > be wrong subsection. > > > > On 16 April 2015 at 16:24, Suman Tripathi <stripa...@apm.com> wrote: > > Try increasing the SWIOTLB size to 128MB .Default is 64MB. > > Ok, so I'm back to k3.18.7 (default in the latest Fatdog), although > I'm not sure what should be the exact value of swiotlb boot param? > Got totally mixed results from uncle Google - some says the unit is in > MiB, some that it's 4k pages and another that 128MiB = 65536, so I > played it safe and used swiotlb=131072. > Is this correct? > It may take a few days, but I'll let you know if it worked (or for how > long, if not). > > > > On 16 April 2015 at 16:54, Alexander Duyck <alexander.du...@gmail.com> wrote: > > More likely would be a device driver that is DMA mapping memory but not > > unmapping it after it is done resulting in the bounce buffer pool being > > depleted. > > You might want dump the list of drivers loaded on the system with lsmod, > > and then possibly look at doing a git bisect for something introduced > > between 3.17 and 3.18 since that seems to be when you started seeing > > this issue. > > Ok, I'll (try to) look at this, but like I said - I'm not a kernel > (nor git) expert. > Anyway, I guess I'm gonna start with this: > https://wiki.gentoo.org/wiki/Kernel_git-bisect > Who knows...perhaps I'll find something...
And easier way is to compile the kernel with CONFIG_DMA_API_DEBUG and then load the attached module. That should tell you who and what else is holding on the buffers. > > > > Thank you all for the replies. > Jake > _______________________________________________ > iommu mailing list > io...@lists.linux-foundation.org > https://lists.linuxfoundation.org/mailman/listinfo/iommu
/* * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License v2.0 as published by * the Free Software Foundation * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ #include <linux/module.h> #include <linux/string.h> #include <linux/types.h> #include <linux/init.h> #include <linux/stat.h> #include <linux/err.h> #include <linux/ctype.h> #include <linux/slab.h> #include <linux/limits.h> #include <linux/device.h> #include <linux/pci.h> #include <linux/blkdev.h> #include <linux/device.h> #include <linux/init.h> #include <linux/mm.h> #include <linux/fcntl.h> #include <linux/slab.h> #include <linux/kmod.h> #include <linux/major.h> #include <linux/highmem.h> #include <linux/blkdev.h> #include <linux/module.h> #include <linux/blkpg.h> #include <linux/buffer_head.h> #include <linux/mpage.h> #include <linux/mount.h> #include <linux/uio.h> #include <linux/namei.h> #include <asm/uaccess.h> #include <linux/pagemap.h> #include <linux/pagevec.h> #include <linux/dma-debug.h> #define DUMP_DMA_FUN "0.1" MODULE_AUTHOR("Konrad Rzeszutek Wilk <konrad@virtualiron>"); MODULE_DESCRIPTION("dump dma"); MODULE_LICENSE("GPL"); MODULE_VERSION(DUMP_DMA_FUN); static int __init dump_dma_init(void) { debug_dma_dump_mappings(NULL); return 0; } static void __exit dump_dma_exit(void) { } module_init(dump_dma_init); module_exit(dump_dma_exit);