pata-macio WARNING at dmam_alloc_coherent+0xec/0x110

pata-macio WARNING at dmam_alloc_coherent+0xec/0x110

[Meelis Roos]

I tested 4.16-rc1 on my PowerMac G4 and got the following warning from 
macio pata driver. Since pata-macio has no recent changes, dma-mapping.h 
changes seem to be related.

[    0.228408] MacIO PCI driver attached to Keylargo chipset
[    1.283931] pata-macio 0.0001f000:ata-4: Activating pata-macio chipset KeyLargo ATA-4, Apple bus ID 2
[    1.284398] WARNING: CPU: 0 PID: 1 at ./include/linux/dma-mapping.h:516 dmam_alloc_coherent+0xec/0x110
[    1.284689] Modules linked in:
[    1.284797] CPU: 0 PID: 1 Comm: swapper Not tainted 4.16.0-rc1 #60
[    1.284991] NIP:  c03259ec LR: c0325948 CTR: 00000000
[    1.285150] REGS: ef047c10 TRAP: 0700   Not tainted  (4.16.0-rc1)
[    1.285337] MSR:  00029032 <EE,ME,IR,DR,RI>  CR: 24fff228  XER: 20000000
[    1.285559] 
               GPR00: c0325948 ef047cc0 ef048000 ef1321b0 00000000 00000000 ef1321bc 00000000 
               GPR08: 00000000 00000000 c04f1bd0 00000000 22fff884 00000000 c0004c80 00000000 
               GPR16: 00000000 00000000 00000000 00000000 00000000 00000000 c0660000 c05f0960 
               GPR24: 00000007 c063d7a8 00000000 ef1e59ac 00001020 ef1321b0 ef135c18 014000c0 
[    1.303085] NIP [c03259ec] dmam_alloc_coherent+0xec/0x110
[    1.308751] LR [c0325948] dmam_alloc_coherent+0x48/0x110
[    1.314511] Call Trace:
[    1.320187] [ef047cc0] [c0325948] dmam_alloc_coherent+0x48/0x110 (unreliable)
[    1.326133] [ef047ce0] [c0370a90] pata_macio_port_start+0x44/0xb8
[    1.332110] [ef047d00] [c0355ed4] ata_host_start.part.5+0x138/0x254
[    1.338100] [ef047d30] [c035c1e8] ata_host_activate+0x84/0x1a0
[    1.344007] [ef047d50] [c0371214] pata_macio_common_init+0x3b0/0x608
[    1.349890] [ef047db0] [c0336f9c] macio_device_probe+0x60/0x120
[    1.355761] [ef047dd0] [c031868c] driver_probe_device+0x25c/0x35c
[    1.361576] [ef047e00] [c031887c] __driver_attach+0xf0/0xf4
[    1.367320] [ef047e20] [c0316340] bus_for_each_dev+0x80/0xc0
[    1.373051] [ef047e50] [c031782c] bus_add_driver+0x144/0x258
[    1.378805] [ef047e70] [c03190dc] driver_register+0x8c/0x140
[    1.384580] [ef047e80] [c060ce14] pata_macio_init+0x5c/0x8c
[    1.390303] [ef047ea0] [c0004aa0] do_one_initcall+0x48/0x18c
[    1.396000] [ef047f00] [c05f1214] kernel_init_freeable+0x12c/0x1ec
[    1.401615] [ef047f30] [c0004c98] kernel_init+0x18/0x128
[    1.407208] [ef047f40] [c00122e4] ret_from_kernel_thread+0x5c/0x64
[    1.412829] Instruction dump:
[    1.418409] 939d0000 4bff6329 80010024 7fe3fb78 8361000c 83810010 7c0803a6 83a10014
[    1.424201] 83c10018 83e1001c 38210020 4e800020 <0fe00000> 4bffff84 7fa3eb78 3be00000 
[    1.430020] ---[ end trace 89c0f4a91a110769 ]---


-- 
Meelis Roos (mroos@linux.ee)

Re: pata-macio WARNING at dmam_alloc_coherent+0xec/0x110

[Christoph Hellwig]

On Mon, Feb 12, 2018 at 10:52:46PM +0200, Meelis Roos wrote:
> I tested 4.16-rc1 on my PowerMac G4 and got the following warning from 
> macio pata driver. Since pata-macio has no recent changes, dma-mapping.h 
> changes seem to be related.

Thje are, as they add just that warning.  But the root cause looks
older, and that is that the macio bus doesn't seem to to set the
dma coherent mask, which could cause all kinds of hidden issues.

I'm travelling right now, but unless someone beats me to it I'll look
into a patch to properly set the coherent mask ASAP.

Re: pata-macio WARNING at dmam_alloc_coherent+0xec/0x110

[Christoph Hellwig]

Does this fix your warning?

diff --git a/drivers/macintosh/macio_asic.c b/drivers/macintosh/macio_asic.c
index 62f541f968f6..07074820a167 100644
--- a/drivers/macintosh/macio_asic.c
+++ b/drivers/macintosh/macio_asic.c
@@ -375,6 +375,7 @@ static struct macio_dev * macio_add_one_device(struct macio_chip *chip,
 	dev->ofdev.dev.of_node = np;
 	dev->ofdev.archdata.dma_mask = 0xffffffffUL;
 	dev->ofdev.dev.dma_mask = &dev->ofdev.archdata.dma_mask;
+	dev->ofdev.dev.coherent_dma_mask = dev->ofdev.archdata.dma_mask;
 	dev->ofdev.dev.parent = parent;
 	dev->ofdev.dev.bus = &macio_bus_type;
 	dev->ofdev.dev.release = macio_release_dev;

Re: pata-macio WARNING at dmam_alloc_coherent+0xec/0x110

[Mathieu Malaterre]

Hi,

On Tue, Feb 13, 2018 at 3:51 PM, Christoph Hellwig <hch@lst.de> wrote:
> Does this fix your warning?
>
> diff --git a/drivers/macintosh/macio_asic.c b/drivers/macintosh/macio_asic.c
> index 62f541f968f6..07074820a167 100644
> --- a/drivers/macintosh/macio_asic.c
> +++ b/drivers/macintosh/macio_asic.c
> @@ -375,6 +375,7 @@ static struct macio_dev * macio_add_one_device(struct macio_chip *chip,
>         dev->ofdev.dev.of_node = np;
>         dev->ofdev.archdata.dma_mask = 0xffffffffUL;
>         dev->ofdev.dev.dma_mask = &dev->ofdev.archdata.dma_mask;
> +       dev->ofdev.dev.coherent_dma_mask = dev->ofdev.archdata.dma_mask;
>         dev->ofdev.dev.parent = parent;
>         dev->ofdev.dev.bus = &macio_bus_type;
>         dev->ofdev.dev.release = macio_release_dev;

Indeed, Thanks much! If needed:

Tested-by: Mathieu Malaterre <malat@debian.org>

System: Mac Mini G4

ref:
https://www.mail-archive.com/linuxppc-dev@lists.ozlabs.org/msg128662.html

Re: pata-macio WARNING at dmam_alloc_coherent+0xec/0x110

[Meelis Roos]

> Does this fix your warning?
> 
> diff --git a/drivers/macintosh/macio_asic.c b/drivers/macintosh/macio_asic.c
> index 62f541f968f6..07074820a167 100644
> --- a/drivers/macintosh/macio_asic.c
> +++ b/drivers/macintosh/macio_asic.c
> @@ -375,6 +375,7 @@ static struct macio_dev * macio_add_one_device(struct macio_chip *chip,
>  	dev->ofdev.dev.of_node = np;
>  	dev->ofdev.archdata.dma_mask = 0xffffffffUL;
>  	dev->ofdev.dev.dma_mask = &dev->ofdev.archdata.dma_mask;
> +	dev->ofdev.dev.coherent_dma_mask = dev->ofdev.archdata.dma_mask;
>  	dev->ofdev.dev.parent = parent;
>  	dev->ofdev.dev.bus = &macio_bus_type;
>  	dev->ofdev.dev.release = macio_release_dev;

Yes, it does - thank you!

Tested-by: Meelis Roos <mroos@linux.ee>

-- 
Meelis Roos (mroos@linux.ee)