On Sat, Oct 5, 2019 at 10:25 AM Christoph Hellwig <h...@lst.de> wrote: > thanks for the patch. I think it would be much easier to just > use the original open coded check in dma_common_free_remap instead > of adding a new helper. What do you think of the version below? > > --- > From 2cf2aa6a69db0b17b3979144287af8775c1c1534 Mon Sep 17 00:00:00 2001 > From: Andrey Smirnov <andrew.smir...@gmail.com> > Date: Sat, 5 Oct 2019 10:23:30 +0200 > Subject: dma-mapping: fix false positivse warnings in dma_common_free_remap() > > Commit 5cf4537975bb ("dma-mapping: introduce a dma_common_find_pages > helper") changed invalid input check in dma_common_free_remap() from: > > if (!area || !area->flags != VM_DMA_COHERENT) > > to > > if (!area || !area->flags != VM_DMA_COHERENT || !area->pages) > > which seem to produce false positives for memory obtained via > dma_common_contiguous_remap() > > This triggers the following warning message when doing "reboot" on ZII > VF610 Dev Board Rev B: > > WARNING: CPU: 0 PID: 1 at kernel/dma/remap.c:112 > dma_common_free_remap+0x88/0x8c > trying to free invalid coherent area: 9ef82980 > Modules linked in: > CPU: 0 PID: 1 Comm: systemd-shutdow Not tainted 5.3.0-rc6-next-20190820 #119 > Hardware name: Freescale Vybrid VF5xx/VF6xx (Device Tree) > Backtrace: > [<8010d1ec>] (dump_backtrace) from [<8010d588>] (show_stack+0x20/0x24) > r7:8015ed78 r6:00000009 r5:00000000 r4:9f4d9b14 > [<8010d568>] (show_stack) from [<8077e3f0>] (dump_stack+0x24/0x28) > [<8077e3cc>] (dump_stack) from [<801197a0>] (__warn.part.3+0xcc/0xe4) > [<801196d4>] (__warn.part.3) from [<80119830>] (warn_slowpath_fmt+0x78/0x94) > r6:00000070 r5:808e540c r4:81c03048 > [<801197bc>] (warn_slowpath_fmt) from [<8015ed78>] > (dma_common_free_remap+0x88/0x8c) > r3:9ef82980 r2:808e53e0 > r7:00001000 r6:a0b1e000 r5:a0b1e000 r4:00001000 > [<8015ecf0>] (dma_common_free_remap) from [<8010fa9c>] > (remap_allocator_free+0x60/0x68) > r5:81c03048 r4:9f4d9b78 > [<8010fa3c>] (remap_allocator_free) from [<801100d0>] > (__arm_dma_free.constprop.3+0xf8/0x148) > r5:81c03048 r4:9ef82900 > [<8010ffd8>] (__arm_dma_free.constprop.3) from [<80110144>] > (arm_dma_free+0x24/0x2c) > r5:9f563410 r4:80110120 > [<80110120>] (arm_dma_free) from [<8015d80c>] (dma_free_attrs+0xa0/0xdc) > [<8015d76c>] (dma_free_attrs) from [<8020f3e4>] (dma_pool_destroy+0xc0/0x154) > r8:9efa8860 r7:808f02f0 r6:808f02d0 r5:9ef82880 r4:9ef82780 > [<8020f324>] (dma_pool_destroy) from [<805525d0>] > (ehci_mem_cleanup+0x6c/0x150) > r7:9f563410 r6:9efa8810 r5:00000000 r4:9efd0148 > [<80552564>] (ehci_mem_cleanup) from [<80558e0c>] (ehci_stop+0xac/0xc0) > r5:9efd0148 r4:9efd0000 > [<80558d60>] (ehci_stop) from [<8053c4bc>] (usb_remove_hcd+0xf4/0x1b0) > r7:9f563410 r6:9efd0074 r5:81c03048 r4:9efd0000 > [<8053c3c8>] (usb_remove_hcd) from [<8056361c>] (host_stop+0x48/0xb8) > r7:9f563410 r6:9efd0000 r5:9f5f4040 r4:9f5f5040 > [<805635d4>] (host_stop) from [<80563d0c>] (ci_hdrc_host_destroy+0x34/0x38) > r7:9f563410 r6:9f5f5040 r5:9efa8800 r4:9f5f4040 > [<80563cd8>] (ci_hdrc_host_destroy) from [<8055ef18>] > (ci_hdrc_remove+0x50/0x10c) > [<8055eec8>] (ci_hdrc_remove) from [<804a2ed8>] > (platform_drv_remove+0x34/0x4c) > r7:9f563410 r6:81c4f99c r5:9efa8810 r4:9efa8810 > [<804a2ea4>] (platform_drv_remove) from [<804a18a8>] > (device_release_driver_internal+0xec/0x19c) > r5:00000000 r4:9efa8810 > [<804a17bc>] (device_release_driver_internal) from [<804a1978>] > (device_release_driver+0x20/0x24) > r7:9f563410 r6:81c41ed0 r5:9efa8810 r4:9f4a1dac > [<804a1958>] (device_release_driver) from [<804a01b8>] > (bus_remove_device+0xdc/0x108) > [<804a00dc>] (bus_remove_device) from [<8049c204>] (device_del+0x150/0x36c) > r7:9f563410 r6:81c03048 r5:9efa8854 r4:9efa8810 > [<8049c0b4>] (device_del) from [<804a3368>] > (platform_device_del.part.2+0x20/0x84) > r10:9f563414 r9:809177e0 r8:81cb07dc r7:81c78320 r6:9f563454 r5:9efa8800 > r4:9efa8800 > [<804a3348>] (platform_device_del.part.2) from [<804a3420>] > (platform_device_unregister+0x28/0x34) > r5:9f563400 r4:9efa8800 > [<804a33f8>] (platform_device_unregister) from [<8055dce0>] > (ci_hdrc_remove_device+0x1c/0x30) > r5:9f563400 r4:00000001 > [<8055dcc4>] (ci_hdrc_remove_device) from [<805652ac>] > (ci_hdrc_imx_remove+0x38/0x118) > r7:81c78320 r6:9f563454 r5:9f563410 r4:9f541010 > [<8056538c>] (ci_hdrc_imx_shutdown) from [<804a2970>] > (platform_drv_shutdown+0x2c/0x30) > [<804a2944>] (platform_drv_shutdown) from [<8049e4fc>] > (device_shutdown+0x158/0x1f0) > [<8049e3a4>] (device_shutdown) from [<8013ac80>] > (kernel_restart_prepare+0x44/0x48) > r10:00000058 r9:9f4d8000 r8:fee1dead r7:379ce700 r6:81c0b280 r5:81c03048 > r4:00000000 > [<8013ac3c>] (kernel_restart_prepare) from [<8013ad14>] > (kernel_restart+0x1c/0x60) > [<8013acf8>] (kernel_restart) from [<8013af84>] (__do_sys_reboot+0xe0/0x1d8) > r5:81c03048 r4:00000000 > [<8013aea4>] (__do_sys_reboot) from [<8013b0ec>] (sys_reboot+0x18/0x1c) > r8:80101204 r7:00000058 r6:00000000 r5:00000000 r4:00000000 > [<8013b0d4>] (sys_reboot) from [<80101000>] (ret_fast_syscall+0x0/0x54) > Exception stack(0x9f4d9fa8 to 0x9f4d9ff0) > 9fa0: 00000000 00000000 fee1dead 28121969 01234567 379ce700 > 9fc0: 00000000 00000000 00000000 00000058 00000000 00000000 00000000 00016d04 > 9fe0: 00028e0c 7ec87c64 000135ec 76c1f410 > > Restore original invalid input check in dma_common_free_remap() to > avoid this problem. > > Fixes: 5cf4537975bb ("dma-mapping: introduce a dma_common_find_pages helper") > Signed-off-by: Andrey Smirnov <andrew.smir...@gmail.com> > [hch: just revert the offending hunk instead of creating a new helper] > Signed-off-by: Christoph Hellwig <h...@lst.de>
Tested-by: Geert Uytterhoeven <geert+rene...@glider.be> Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu