Re: [Qemu-devel] qemu git head 20100323 on FreeBSD - qemu-devel port update for testing

[Blue Swirl <blauwirbel@gmail.com>]

On 3/30/10, Juergen Lock <nox@jelal.kn-bremen.de> wrote:
> On Tue, Mar 30, 2010 at 09:04:28PM +0300, Blue Swirl wrote:
>  > On 3/25/10, Juergen Lock <nox@jelal.kn-bremen.de> wrote:
>  > > Hi!
>  > >
>  > >   Now that qemu git head works again (thanx Aurelien! :) I've finished
>  > >  the FreeBSD qemu-devel port update patch/shar that made me uncover
>  > >  the bug:
>  > >         http://people.freebsd.org/~nox/qemu/qemu-devel-20100323.patch
>  > >  resp.
>  > >         http://people.freebsd.org/~nox/qemu/qemu-devel-20100323.shar
>  > >
>  > >   This also adds a few misc fixes (that I'll submit on the qemu list
>  > >  seperately), I have...
>  > >
>  > >  . Fixed the FreeBSD executable path detection to work without /proc
>  > >   mounted (it usually isn't on FreeBSD), so you now no longer have to
>  > >   pass the path to the pc-bios dir with -L if you run qemu out of the
>  > >   build dir when another version is installed, like,
>  > >         work/qemu-snapshot-20100323_20/i386-softmmu/qemu ...
>  > >
>  > >   (files/patch-vl.c in the shar/patch)
>  > >
>  > >  . Fixed some more bsd-user bugs so all of i386-bsd-user, x86_64-bsd-user,
>  > >   and sparc64-bsd-user now run for me again on FreeBSD stable/8 amd64.
>  > >   (I didn't test sparc-bsd-user as I only tried -bsd freebsd and FreeBSD
>  > >   doesn't run on 32bit sparc.) - Yes bsd-user still needs more work but
>  > >   at least simple exectuables run.
>  > >
>  > >   (files/patch-bsd-user-mmap.c, files/patch-exec.c)
>  > >
>  > >  . Fixed the bsd-user host page protection code for FreeBSD hosts
>  > >   (using kinfo_getvmmap(3) on FeeBSD >= 7.x and /compat/linux/proc
>  > >   on older FreeBSD.)
>  > >
>  > >   (files/patch-bsd-user-linproc)
>  > >
>  > >  . Fixed some compilation warnings and a missing #include.
>  > >
>  > >   (files/patch-qemu-char.c, files/patch-qemu-timer.c)
>  > >
>  >
>  > Thanks, applied all except exec.c one.
>
>
> Oh, is there something wrong with it?  You mean this one, right?
>
>  Subject: [PATCH] Avoid page_set_flags() assert in qemu-user host page
>   protection code
>  Message-ID: <20100325211421.GA52572@triton8.kn-bremen.de>
>  [...]
>
>  --- a/exec.c
>  +++ b/exec.c
>  @@ -293,10 +293,13 @@ static void page_init(void)
>
>                      if (h2g_valid(endaddr)) {
>                          endaddr = h2g(endaddr);
>  +                        page_set_flags(startaddr, endaddr, PAGE_RESERVED);
>                      } else {
>  +#if TARGET_ABI_BITS <= L1_MAP_ADDR_SPACE_BITS
>                          endaddr = ~0ul;
>  +                        page_set_flags(startaddr, endaddr, PAGE_RESERVED);
>  +#endif
>                      }
>  -                    page_set_flags(startaddr, endaddr, PAGE_RESERVED);
>                  }
>              } while (!feof(f));
>
>   I first tried to replace the endaddr in the !h2g_valid(endaddr) case with
>         ((abi_ulong)1 << L1_MAP_ADDR_SPACE_BITS) - 1
>  if TARGET_ABI_BITS > L1_MAP_ADDR_SPACE_BITS (which comes from the condition
>  of the assert in page_set_flags() that was triggered on the ~0ul value),
>  but that caused the qemu process to grow into swap and made the box
>  usuable when that code was reached and I had to kill qemu.  (The box has
>  8 GB RAM.)  And so I thought just leaving that page range unprotected
>  if only the start address is valid was the lesser evil...

I was thinking something like (abi_ulong)-1 but maybe that isn't any
more correct.