I think this broke core dumps on mips ...
On Sun, Aug 23, 2009 at 03:38:19AM +0000, Matt Thomas wrote:
> Module Name: src
> Committed By: matt
> Date: Sun Aug 23 03:38:19 UTC 2009
>
> Modified Files:
> src/sys/arch/mips/include [matt-nb5-mips64]: types.h
> src/sys/arch/mips/mips [matt-nb5-mips64]: mips_machdep.c
> process_machdep.c
> src/sys/kern [matt-nb5-mips64]: core_elf32.c sys_process.c
> src/sys/sys [matt-nb5-mips64]: ptrace.h
>
> Log Message:
> Change lazy fp load/save is done. fpcurlwp is never NULL.
> If no current lwp has the FP, then fpcurlwp is set to lwp0.
> this allows many check for NULL and avoids a few null-derefs.
> Since savefpregs clear COP1, loadfpregs can be called to reload
> fpregs. If it notices that situation, it just sets COP1 and returns
> Save does not reset fpcurlwp, just clears COP1. load does set fpcurlwp.
>
> If MIPS3_SR_FR is set, all 32 64-bit FP registers are saved/restored via Xdc1.
> If MIPS3_SR_FR is clear, only 32 32-bit FP register are saved/restore via
> Xwc1.
> This preserves the existing ABI.
>
>
> To generate a diff of this commit:
> cvs rdiff -u -r1.43.36.2 -r1.43.36.3 src/sys/arch/mips/include/types.h
> cvs rdiff -u -r1.205.4.1.2.1.2.2 -r1.205.4.1.2.1.2.3 \
> src/sys/arch/mips/mips/mips_machdep.c
> cvs rdiff -u -r1.29.62.1 -r1.29.62.2 src/sys/arch/mips/mips/process_machdep.c
> cvs rdiff -u -r1.32.16.1 -r1.32.16.2 src/sys/kern/core_elf32.c
> cvs rdiff -u -r1.143.4.1 -r1.143.4.1.4.1 src/sys/kern/sys_process.c
> cvs rdiff -u -r1.40 -r1.40.28.1 src/sys/sys/ptrace.h
>
> Please note that diffs are not public domain; they are subject to the
> copyright notices on the relevant files.
>
The change to core_elf32.c is mostly:
@@ -452,14 +456,19 @@ ELFNAMEEND(coredump_note)(struct proc *p
#ifdef PT_GETFPREGS
notesize = sizeof(nhdr) + elfround(namesize) + elfround(sizeof(freg));
if (iocookie) {
+ size_t freglen = sizeof(freg);
uvm_lwp_hold(l);
+#ifdef __HAVE_PROCESS_XFPREGS
+ error = elf_process_read_xfpregs(l, &freg, &freglen);
+#else
error = elf_process_read_fpregs(l, &freg);
+#endif
uvm_lwp_rele(l);
if (error)
return (error);
nhdr.n_namesz = namesize;
- nhdr.n_descsz = sizeof(freg);
+ nhdr.n_descsz = freglen;
nhdr.n_type = PT_GETFPREGS;
error = ELFNAMEEND(coredump_writenote)(p, iocookie, &nhdr,
However this code is called twice, once with iocookie == NULL in order
to find out how big everything will be, then again with iocookie != NULL
to actually do the writes.
So changing the size of the register area on the second pass is going to
lead to corrupt core files.
David
--
David Laight: da...@l8s.co.uk
