From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alexey Starikovskiy <aystarik@gmail.com>
Subject: Re: ISA -> ISA_ (Re: [GIT PATCH] ACPI patches for 2.6.25-rc6)
Date: Wed, 26 Mar 2008 20:24:41 +0300
Message-ID: <47EA86D9.7040404@gmail.com>
References: <200803180510.47670.lenb@kernel.org> <20080326081653.GA8247@elte.hu> <200803261132.21448.lenb@kernel.org> <200803260956.55804.bjorn.helgaas@hp.com>
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To: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Len Brown <lenb@kernel.org>, Ingo Molnar <mingo@elte.hu>, Corentin CHARY <corentincj@iksaif.net>, Linus Torvalds <torvalds@linux-foundation.org>, Andrew Morton <akpm@linux-foundation.org>, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pm@lists.linux-foundation.org

Bjorn Helgaas wrote:
> I'm curious about how this works.  I disassembled the DSDT from
> http://bugzilla.kernel.org/show_bug.cgi?id=4773 (I attached the disassembly
> at http://bugzilla.kernel.org/attachment.cgi?id=15448&action=view), and
> the _PRT contains "_SB" and "ISA" (no trailing underscores):
>
>                 Package (0x04)
>                 {
>                     0x000DFFFF, 
>                     0x00, 
>                     \_SB.PCI0.ISA.LNKA, 
>                     0x00
>                 }
>
> But by the time we get to acpi_pci_irq_add_entry(), we've added the
> underscores somewhere (see
> http://bugzilla.kernel.org/attachment.cgi?id=15423&action=view):
>
>   0000:00:0d[A] -> \_SB_.PCI0.ISA_.LNKA
>
> I don't know where this happens, but it certainly confused me, and
> it seems like it could lead to other bugs.
>   
ACPI is supposed to add trailing underscore for pad all names to 4 bytes.
So ISA will be padded to ISA_.

Regards,
Alex.