Re: [parisc-linux] Boot error on C200+

[David Huggins-Daines <dhd@linuxcare.com>]

Ryan Bradetich <rbradetich@uswest.net> writes:

> > Note that GR20 is 0x37, which is the syscall number for fcntl(), which
> > confirms your earlier findings :-)
> 
> From arch/parisc/kernel/syscall.S
> 
>         ENTRY_NAME(sys_ioctl)
>         ENTRY_NAME(sys_fcntl)           /* 55 */
>         ENTRY_NAME(sys_socketpair)
> 
> 55 = 0x37 ....  I understand that....I don't see where GR20 is mapped to the
> the syscall number.... (Not really important that I know now... but curious)

A system call on PA-RISC Linux looks like this:

        be,l    0x100(%sr2,%r0),%sr0,%r31
        ldi     <syscall number>,%r20

(with six possible arguments in %r26 - %r21)

> From this statement, I assume it is a kernel problem and not a glibc
> problem ... since the kernel would perform the mapping?  I'll start digging
> around in the kernel and see what I can find.... any hints where to start?

I think the explanation regarding the TLB miss handlers is correct,
but I haven't tried on the C360 since it doesn't get to userland for
me :(

-- 
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