Re: [PATCH v2 2/3] tpm-ppi: page-align PPI RAM

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Dr. David Alan Gilbert (dgilbert@redhat.com) wrote:
> * Marc-André Lureau (marcandre.lureau@redhat.com) wrote:
> > post-copy migration fails on destination with error such as:
> > 2019-12-26T10:22:44.714644Z qemu-kvm: ram_block_discard_range:
> > Unaligned start address: 0x559d2afae9a0
> 
> Ah good, we got a sane error message!
> 
> > Use qemu_memalign() to constrain the PPI RAM memory alignment.
> > 
> > Cc: qemu-stable@nongnu.org
> > Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> > Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> > ---
> >  hw/tpm/tpm_ppi.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> > 
> > diff --git a/hw/tpm/tpm_ppi.c b/hw/tpm/tpm_ppi.c
> > index ff314592b4..6d9c1a3e40 100644
> > --- a/hw/tpm/tpm_ppi.c
> > +++ b/hw/tpm/tpm_ppi.c
> > @@ -43,7 +43,8 @@ void tpm_ppi_reset(TPMPPI *tpmppi)
> >  void tpm_ppi_init(TPMPPI *tpmppi, struct MemoryRegion *m,
> >                    hwaddr addr, Object *obj)
> >  {
> > -    tpmppi->buf = g_malloc0(HOST_PAGE_ALIGN(TPM_PPI_ADDR_SIZE));
> > +    tpmppi->buf = qemu_memalign(qemu_real_host_page_size,
> > +                                HOST_PAGE_ALIGN(TPM_PPI_ADDR_SIZE));
> 
> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

I just noticed a bit in the CODING_STYLE that says:

  Memory allocated by qemu_memalign or qemu_blockalign must be freed with
  qemu_vfree, since breaking this will cause problems on Win32.

so I guess this is wrong?

Dave

> 
> >      memory_region_init_ram_device_ptr(&tpmppi->ram, obj, "tpm-ppi",
> >                                        TPM_PPI_ADDR_SIZE, tpmppi->buf);
> >      vmstate_register_ram(&tpmppi->ram, DEVICE(obj));
> > -- 
> > 2.24.0.308.g228f53135a
> > 
> --
> Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK