Re: [PATCH 1/3] dma-direct: unify the dma_capable definitions

On Tue, 19 Nov 2019 at 17:27, Marek Szyprowski [off-list ref] wrote:

Hi Christoph,

On 13.11.2019 08:35, Christoph Hellwig wrote:

quoted

Currently each architectures that wants to override dma_to_phys and
phys_to_dma also has to provide dma_capable.  But there isn't really
any good reason for that.  powerpc and mips just have copies of the
generic one minus the latests fix, and the arm one was the inspiration
for said fix, but misses the bus_dma_mask handling.
Make all architectures use the generic version instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>

This patch breaks DMAengine PL330 driver on Samsung Exynos SoCs:

Thanks Marek for bisecting it. I wonder whether it is also the cause
for boot failures I see on NXP Vybrid VF50 SoC (NXP/Freescale
fsl-edma) since few days:

[ 2.853428] fsl-edma 40018000.dma-controller: overflow 0x40027007+1 of
DMA mask ffffffff bus mask 0
[ 2.862566] ------------[ cut here ]------------
[ 2.867273] WARNING: CPU: 0 PID: 1 at
/home/buildbot/worker/builddir_yocto/build/build/tmp/work-shared/col-vf50-proceq-mainline-next/kernel-source/kernel/dma/direct.c:35
report_addr+0xc0/0xfc
[ 2.884380] Modules linked in:
[ 2.887486] CPU: 0 PID: 1 Comm: swapper Tainted: G W
5.4.0-rc7-next-20191118-g519ead8f6a32 #1
[ 2.897364] Hardware name: Freescale Vybrid VF5xx/VF6xx (Device Tree)
[ 2.903892] [<8010ddfc>] (unwind_backtrace) from [<8010b4b8>]
(show_stack+0x10/0x14)
[ 2.911712] [<8010b4b8>] (show_stack) from [<8011b08c>] (__warn+0xd4/0xec)
[ 2.918653] [<8011b08c>] (__warn) from [<8011b154>]
(warn_slowpath_fmt+0xb0/0xb8)
[ 2.926218] [<8011b154>] (warn_slowpath_fmt) from [<80155f7c>]
(report_addr+0xc0/0xfc)
[ 2.934221] [<80155f7c>] (report_addr) from [<801561f0>]
(dma_direct_map_resource+0x98/0xa4)
[ 2.942744] [<801561f0>] (dma_direct_map_resource) from [<8041d5d4>]
(fsl_edma_prep_slave_dma+0x12c/0x150)
[ 2.952475] [<8041d5d4>] (fsl_edma_prep_slave_dma) from [<8041d8cc>]
(fsl_edma_prep_dma_cyclic+0x30/0x21c)
[ 2.962213] [<8041d8cc>] (fsl_edma_prep_dma_cyclic) from [<80452e10>]
(lpuart_rx_dma_startup+0x188/0x36c)
[ 2.971871] [<80452e10>] (lpuart_rx_dma_startup) from [<80453058>]
(lpuart_startup+0x64/0x78)
[ 2.980477] [<80453058>] (lpuart_startup) from [<8044e924>]
(uart_startup.part.7+0x110/0x23c)
[ 2.989080] [<8044e924>] (uart_startup.part.7) from [<8044eaa0>]
(uart_port_activate+0x50/0x7c)
[ 2.997857] [<8044eaa0>] (uart_port_activate) from [<80438dc0>]
(tty_port_open+0x74/0xc0)
[ 3.006111] [<80438dc0>] (tty_port_open) from [<8044be30>] (uart_open+0x18/0x20)
[ 3.013588] [<8044be30>] (uart_open) from [<80431b4c>] (tty_open+0x108/0x428)
[ 3.020794] [<80431b4c>] (tty_open) from [<801edb48>] (chrdev_open+0xac/0x164)
[ 3.028098] [<801edb48>] (chrdev_open) from [<801e55c8>]
(do_dentry_open+0x22c/0x3e4)
[ 3.036010] [<801e55c8>] (do_dentry_open) from [<801f72a8>]
(path_openat+0x4a4/0xf78)
[ 3.043912] [<801f72a8>] (path_openat) from [<801f8d34>]
(do_filp_open+0x70/0xdc)
[ 3.051472] [<801f8d34>] (do_filp_open) from [<801e6998>]
(do_sys_open+0x128/0x1f4)
[ 3.059217] [<801e6998>] (do_sys_open) from [<80a00ee0>]
(kernel_init_freeable+0x150/0x1c4)
[ 3.067658] [<80a00ee0>] (kernel_init_freeable) from [<8068e208>]
(kernel_init+0x8/0x110)
[ 3.075917] [<8068e208>] (kernel_init) from [<801010e8>]
(ret_from_fork+0x14/0x2c)
[ 3.083539] Exception stack(0x86843fb0 to 0x86843ff8)
[ 3.088631] 3fa0: 00000000 00000000 00000000 00000000
[ 3.096866] 3fc0: 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000
[ 3.105103] 3fe0: 00000000 00000000 00000000 00000000 00000013 00000000
[ 3.111752] ---[ end trace 6fb699802256a309 ]---
[    3.116423] fsl-lpuart 40027000.serial: Cannot prepare cyclic DMA
[    3.192968] VFS: Mounted root (nfs4 filesystem) on device 0:13.
[    3.201432] devtmpfs: mounted
[    3.210985] Freeing unused kernel memory: 1024K
[    3.217854] Run /sbin/init as init process
[    4.643355] systemd[1]: System time before build time, advancing clock.
[    4.774106] random: systemd: uninitialized urandom read (16 bytes read)
[    4.838361] systemd[1]: systemd 232 running in system mode. (-PAM
-AUDIT -SELINUX -IMA -APPARMOR -SMACK +SYSVINIT +UTMP -LIBCRYPTSETUP
-GCRYPT -GNUTLS +ACL +XZ -LZ4 -SECCOMP +BLKID -ELFUTILS +KMOD -IDN)
[    4.858997] systemd[1]: Detected architecture arm.
[    4.873438] fsl-lpuart 40027000.serial: Cannot prepare TX slave DMA!
[    4.880138] fsl-lpuart 40027000.serial: Cannot prepare TX slave DMA!
[    4.886585] fsl-lpuart 40027000.serial: Cannot prepare TX slave DMA!
[    4.893124] fsl-lpuart 40027000.serial: Cannot prepare TX slave DMA!
[    4.899679] fsl-lpuart 40027000.serial: Cannot prepare TX slave DMA!
[    4.906110] fsl-lpuart 40027000.serial: Cannot prepare TX slave DMA!
[    4.912616] fsl-lpuart 40027000.serial: Cannot prepare TX slave DMA!

Although maybe that's just the fsl-edma problem?

Best regards,
Krzysztof