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| author | peter <peter@FreeBSD.org> | 2003-06-02 21:56:08 +0000 |
|---|---|---|
| committer | peter <peter@FreeBSD.org> | 2003-06-02 21:56:08 +0000 |
| commit | 54294f1739a4b46f029cab4511f55cd9eba1b196 (patch) | |
| tree | 8afdc45e166e9dbfabb5cc78ea699d5505295862 /sys/amd64 | |
| parent | 458ad34341ff5b8d4e26424d48fdb0e21d5c67eb (diff) | |
| download | FreeBSD-src-54294f1739a4b46f029cab4511f55cd9eba1b196.zip FreeBSD-src-54294f1739a4b46f029cab4511f55cd9eba1b196.tar.gz | |
Fix restarted syscalls. When we rewind %rip, we also need to restore
all the argument registers etc since we have almost certainly have trashed
them by now. Take particular car of %r10 since it held the original value
of %rcx (which we saved in tf_rcx on entry and doreti doesn't know this).
Diffstat (limited to 'sys/amd64')
| -rw-r--r-- | sys/amd64/amd64/trap.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/sys/amd64/amd64/trap.c b/sys/amd64/amd64/trap.c index 72ba590..c4e7f16 100644 --- a/sys/amd64/amd64/trap.c +++ b/sys/amd64/amd64/trap.c @@ -751,10 +751,14 @@ syscall(frame) case ERESTART: /* - * Reconstruct pc, assuming lcall $X,y is 7 bytes, - * int 0x80 is 2 bytes. We saved this in tf_err. + * Reconstruct pc, we know that 'syscall' is 2 bytes. + * We have to do a full context restore so that %r10 + * (which was holding the value of %rcx) is restored for + * the next iteration. */ frame.tf_rip -= frame.tf_err; + frame.tf_r10 = frame.tf_rcx; + td->td_pcb->pcb_flags |= PCB_FULLCTX; break; case EJUSTRETURN: |
