Re: [PATCH 5/6] driver core: lift dma_default_coherent into common code

[Maciej W. Rozycki]

On Mon, 15 Feb 2021, Maciej W. Rozycki wrote:

>  I hope to have the adapter properly fixed soon and I'll look at the Malta 
> side now, possibly using the old server whose DEFPA has worked flawlessly 
> for some 20 years now.  I have planned to use the interface to supply NFS 
> root, which I think should be enough of a stress test.

 Card reworked now and network wired, so using the new server actually.  
I haven't booted Linux on my Malta for a while now, but it turns out to 
work just fine, and your patch set does not regress it booting multi-user 
NFS-rooted over FDDI.

 I note however that the system does not reboot properly:

sd 0:0:0:0: [sda] Synchronizing SCSI cache
reboot: Restarting system
Reboot failed -- System halted

which is a regression, and also the MMIO-mapped discrete CBUS UART (ttyS2) 
does not sign in anymore either:

Serial: 8250/16550 driver, 5 ports, IRQ sharing enabled
printk: console [ttyS0] disabled
serial8250.0: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A
printk: console [ttyS0] enabled
printk: console [ttyS0] enabled
printk: bootconsole [uart8250] disabled
printk: bootconsole [uart8250] disabled
serial8250.0: ttyS1 at I/O 0x2f8 (irq = 3, base_baud = 115200) is a 16550A

while long ago:

Serial driver version 5.05c (2001-07-08) with MANY_PORTS SHARE_IRQ SERIAL_PCI enabled
ttyS28 at 0x03f8 (irq = 4) is a 16550A
ttyS29 at 0x02f8 (irq = 3) is a 16550A
ttyS30 at 0x0000 (irq = 20) is a 16550

(I don't know why the line numbers reported were so odd back then, but the 
standard character device major:minor numbers for ttyS0-2 just worked), so 
there's probably something wrong with platform device registration.  ISTR 
using the CBUS UART as a console device at one point too.

  Maciej