the register values coming back from sigreturn(2). Normally this wouldn't
matter because the 32 bit environment would truncate the upper 32 bits
and re-save the truncated values at the next trap. However, if we got
a fast second signal and it was pending while we were returning from
sigreturn(2) in the signal trampoline, we'd never have had a chance to
truncate the bogus values in 32 bit mode, and the new sendsig would get
an EFAULT when trying to write to the bogus user stack address.
is highly MD in an emulation environment since it operates on the host
environment. Although the setregs functions are really for exec support
rather than signals, they deal with the same sorts of context and include
files. So I put it there rather than create yet another file.
structures come out the right size.
Fix the ones that broke. stat32 had some missing fields from the end
and statfs32 was broken due to the strange definition of MNAMELEN
(which is dependent on sizeof(long))
I'm not sure if this fixes any actual problems or not.
stolen from the ia64/ia32 code (indeed there was a repocopy), but I've
redone the MD parts and added and fixed a few essential syscalls. It
is sufficient to run i386 binaries like /bin/ls, /usr/bin/id (dynamic)
and p4. The ia64 code has not implemented signal delivery, so I had
to do that.
Before you say it, yes, this does need to go in a common place. But
we're in a freeze at the moment and I didn't want to risk breaking ia64.
I will sort this out after the freeze so that the common code is in a
common place.
On the AMD64 side, this required adding segment selector context switch
support and some other support infrastructure. The %fs/%gs etc code
is hairy because loading %gs will clobber the kernel's current MSR_GSBASE
setting. The segment selectors are not used by the kernel, so they're only
changed at context switch time or when changing modes. This still needs
to be optimized.
Approved by: re (amd64/* blanket)
