Re: [lm-sensors] 2.6.24-rc4 hwmon it87 probe fails

[Adrian Bunk <bunk@stusta.de>]

On Sun, Dec 09, 2007 at 04:12:25PM -0500, Elvis Pranskevichus wrote:
> Jean Delvare wrote:
> 
> > Hi Mike,
> > 
> > On Sat, 8 Dec 2007 21:22:34 -0500, Mike Houston wrote:
> >> On Sun, 9 Dec 2007 01:05:54 +0100
> >> Adrian Bunk <bunk@stusta.de> wrote:
> >> 
> >> > On Tue, Dec 04, 2007 at 09:51:54PM -0500, Mike Houston wrote:
> >> > > I finally got around to testing Linux 2.6.24 (2.6.24-rc4) and
> >> > > found that the it87 driver fails to probe and consequently, my
> >> > > sensors no longer work. This was fine with Linux 2.6.23.8 (the
> >> > > last kernel I was using)
> >> > > 
> >> > > The necessary modules load, but:
> >> > > 
> >> > > it87: Found IT8718F chip at 0x290, revision 2
> >> > > it87: in3 is VCC (+5V)
> >> > > it87 it87.656: Failed to request region 0x290-0x297
> >> > > it87: probe of it87.656 failed with error -16
> >> > > 
> >> > > Coretemp still works.
> >> > > 
> >> > > It appears it has something to do with the ioport range being
> >> > > reserved for some reason:
> >> > > 
> >> > > system 00:01: ioport range 0x290-0x29f has been reserved
> >> 
> >> > 
> >> > Thanks for your report.
> >> > 
> >> > Please also provide:
> >> > - dmesg from 2.6.23.8
> >> > - The output of "cat /proc/ioports" for both kernels
> >> 
> >> Thanks Adrian, here is the information you have requested, for
> >> both kernels (I have 2.6.23.9 now though where it87 still works)
> >> 
> >> Linux 2.6.23.9:
> >> http://www.mikeserv.com/temp/proc_ioports-2.6.23.9.txt
> >> http://www.mikeserv.com/temp/dmesg-2.6.23.9.txt
> >> http://www.mikeserv.com/temp/config-2.6.23.9.txt
> >> 
> >> Linux 2.6.24-rc4:
> >> http://www.mikeserv.com/temp/proc_ioports-2.6.24-rc4.txt
> >> http://www.mikeserv.com/temp/dmesg-2.6.24-rc4.txt
> > 
> > This one shows:
> > 
> > system 00:01: ioport range 0x290-0x29f has been reserved
> > (...)
> > system 00:01: ioport range 0x290-0x294 has been reserved
> > 
> > This is clearly not correct as both areas overlap. The second
> > reservation is responsible for the it87 breakage, because it conflicts
> > with what the it87 driver later attempts to request (0x290-0x297). The
> > first is wrong as well (the IT87xxF environment controller I/O area is
> > 8 port wide, not 16) but shouldn't be a problem in practice.
> > 
> > These port reservations weren't happening in 2.6.23.9 according to your
> > dmesg output for that kernel. I don't know what changed in this area
> > since 2.6.23.9, maybe Bjorn or Adam (Cc'd) can tell.
> > 
> 
> Hi,
> 
> I have exactly the same problem here on a Gigabyte GA-965G-DS3 motherboard
> based box:
> 
> it87: Found IT8718F chip at 0x290, revision 1
> it87: in3 is VCC (+5V)
> it87 it87.656: Failed to request region 0x290-0x297
> it87: probe of it87.656 failed with error -16
> 
> git bisecting revealed the offending commit:
> 
> a7839e960675b54: PNP: increase the maximum number of resources
> 
> Happened between rc3 and rc4.

Thanks for doing the work of bisecting!

> > Either way, the overlapping areas smell like a BIOS bug, meaning that
> > you should look for an updated BIOS for your system first.
> > 
> >> http://www.mikeserv.com/temp/config-2.6.24-rc4.txt
> > 
> 
> This indeed looks like a broken ACPI BIOS since the aforementioned commit
> touches only the PNP ACPI driver. I'm not sure how to work around this,
> though. Ideas?

People responsible for this commit + ACPI maintainer added to Cc.

>           Elvis

cu
Adrian

-- 

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