--- Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote: > On Sat, 12 May 2007 07:04:25 -0700 (PDT) Tear <tarrqt@xxxxxxxxx> wrote: > > > Summary: If ACPI is not enabled but APIC is, > > then there is trouble on Dell Optiplex GX240. > > If both are enabled or if both are disabled, then > > everything is fine. The attached patch removes > > Dell Optiplex GX240 from the ACPI blacklist. > > > > --- > > > > Hello, > > > > I have a Dell Optiplex GX240 and when I boot Linux, ACPI > > gets set up by only acpi=ht. dmesg shows the following line: > > > > DELL GX240 detected: force use of acpi=ht > > > > Everything seemed to be fine. However, I discovered that > > everything is not fine. The USB controller works so slowly > > that copying a few (uncached) 1 megabyte large photos from > > a USB-enabled digital camera takes many minutes instead of > > a couple of seconds. > > > > I am using Linux 2.6.21.1 on a Debian 4.0 ("Etch") system. > > > > I thought that this might be related to ACPI. So I tried > > to boot with _only_ "acpi=force" appended to the kernel > > command line. Voila, the USB controller started to work > > at full speed and copying photos from my digital camera > > took only seconds. > > > > I tested the system with "acpi=force" and could not find > > anything which did not work. So, can we please remove > > Dell Optiplex GX240 from the blacklist in > > > > ..../arch/i386/kernel/acpi/boot.c > > > > ? The attached patch does just that: It removes Dell > > Optiplex GX240 from the ACPI blacklist. > > > > I thought that this might be related to interrupts and > > APIC as well. (Note that this is APIC, not ACPI.) I tried > > booting with _only_ "noapic" and "nolapic" appended to the > > command line. Again, the USB controller started to work > > at full speed. > > > > If removing Dell Optiplex GX240 from the ACPI blacklist > > is not wanted/possible, then is there a way to disable > > APIC and LAPIC (note that this is APIC not ACPI) by > > default on Dell GX240 machines? (I.e. Can one patch > > the kernel so that APIC and LAPIC isn't used on > > these machines? - I know that I can use the noapic > > and nolapic options on the kernel command line.) > > > > Thank you for your attention. > > > > - Tear > > > > Note: Please include me in CC of your replies. > > > > > > --- linux-2.6.21.1.orig/arch/i386/kernel/acpi/boot.c 2007-05-01 17:10:30.000000000 +0300 > > +++ linux-2.6.21.1/arch/i386/kernel/acpi/boot.c 2007-05-01 20:31:53.000000000 +0300 > > @@ -971,14 +971,6 @@ > > }, > > { > > .callback = force_acpi_ht, > > - .ident = "DELL GX240", > > - .matches = { > > - DMI_MATCH(DMI_BOARD_VENDOR, "Dell Computer Corporation"), > > - DMI_MATCH(DMI_BOARD_NAME, "OptiPlex GX240"), > > - }, > > - }, > > - { > > - .callback = force_acpi_ht, > > .ident = "HP VISUALIZE NT Workstation", > > .matches = { > > DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"), > > > > Thanks. Let's cc the acpi list. > > The origin of that blacklist entry appears to be lost in the mists of time. > git-blame got tripped up by an intervening Lindent run and my gittiness > is insufficient for tracking changes before that. > Mr. Morton, I have already sent a very similar e-mail to the linux-acpi mailing list. Please see the following for that: http://marc.info/?l=linux-acpi&m=117856470816834&w=2 I haven't received a reply and that is why sent this e-mail to the linux-kernel mailing list. I would be very pleased to see the removal of Dell Optiplex GX240 from the ACPI blacklist. Is there a blacklist for APIC? (Note that this is APIC, not ACPI.) Thank you. Tear ____________________________________________________________________________________Boardwalk for $500? In 2007? Ha! Play Monopoly Here and Now (it's updated for today's economy) at Yahoo! Games. http://get.games.yahoo.com/proddesc?gamekey=monopolyherenow - To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html