On Tue, 21 Nov 2017 16:47:11 +0200 "Michael S. Tsirkin" <m...@redhat.com> wrote:
> On Tue, Nov 21, 2017 at 02:26:39PM +0100, Igor Mammedov wrote: > > On Mon, 20 Nov 2017 22:32:29 +0200 > > "Michael S. Tsirkin" <m...@redhat.com> wrote: > > > > > On Mon, Nov 20, 2017 at 05:55:22PM +0100, Igor Mammedov wrote: > > > > On Thu, 16 Nov 2017 13:17:02 +0100 > > > > Thomas Huth <th...@redhat.com> wrote: > > > > > > > > > The bios-tables-test was writing out files that we pass to iasl in > > > > > with the wrong endianness in the header when running on a big endian > > > > > host. So instead of storing mixed endian information in our > > > > > structures, > > > > > let's keep everything in little endian and byte-swap it only when we > > > > > need a value in the code. > > > > > > > > > > Reported-by: Daniel P. Berrange <berra...@redhat.com> > > > > > Buglink: https://bugs.launchpad.net/qemu/+bug/1724570 > > > > > Suggested-by: Michael S. Tsirkin <m...@redhat.com> > > > > > Signed-off-by: Thomas Huth <th...@redhat.com> > > > > > --- > > > > > v2: Fixed vmgenid-test which was accidentially broken in v1 > > > > > > > > > > tests/acpi-utils.h | 27 +++++---------------------- > > > > > tests/bios-tables-test.c | 42 > > > > > ++++++++++++++++++++++-------------------- > > > > > tests/vmgenid-test.c | 22 ++++++++++++---------- > > > > > 3 files changed, 39 insertions(+), 52 deletions(-) > > > > > > > > > > diff --git a/tests/acpi-utils.h b/tests/acpi-utils.h > > > > > index f8d8723..d5ca5b6 100644 > > > > > --- a/tests/acpi-utils.h > > > > > +++ b/tests/acpi-utils.h > > > > > @@ -28,24 +28,9 @@ typedef struct { > > > > > bool tmp_files_retain; /* do not delete the temp asl/aml */ > > > > > } AcpiSdtTable; > > > > > > > > > > -#define ACPI_READ_FIELD(field, addr) \ > > > > > - do { \ > > > > > - switch (sizeof(field)) { \ > > > > > - case 1: \ > > > > > - field = readb(addr); \ > > > > > - break; \ > > > > > - case 2: \ > > > > > - field = readw(addr); \ > > > > > - break; \ > > > > > - case 4: \ > > > > > - field = readl(addr); \ > > > > > - break; \ > > > > > - case 8: \ > > > > > - field = readq(addr); \ > > > > > - break; \ > > > > > - default: \ > > > > > - g_assert(false); \ > > > > > - } \ > > > > probably it's been discussed but, why not do > > > > leXX_to_cpu() > > > > here, instead of making each place that access read field > > > > to do leXX_to_cpu() manually.? > > > > > > > > Beside of keeping access to structure in natural host order, > > > > it should also be less error-prone as field users don't > > > > have to worry about endianness. > > > > > > Yes, I suggested that. > > > The issue is that we don't byte-swap all of the tables > > > (we can't, that would require a full ACPI parser). > > > So when byte-swapping we end up with a mixed host/LE > > > structures. ... > > What tables/use-cases do you have in mind where we'd need full > > ACPI parser /whatever it is/? > > We dump ACPI tables for parsing by iasl. I don't really see a problem here (i.e. how dumping blobs for iasl would require byte-swap all of the tables). Where bios-tables-test.c is concerned we should just read a blob from qemu (get its location/len/name) and dump it to disk without changing anything in it. > > > > > Keeping it all LE seems cleaner. > > > > > >