| Message ID | 1483639302-3084-1-git-send-email-andrew.cooper3@citrix.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 01/05/2017 01:01 PM, Andrew Cooper wrote: > GCCs of at least 4.4 and earlier do not tollerate the initialisiation of the > $VENDOR_cpu_dev structures, because of c_ident becoming an anonymous union. > > Instead of using an anonymous union, reintepret c_ident[] in its CPUID form > just in get_cpu_vendor(). > > Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> > --- > CC: Jan Beulich <JBeulich@suse.com> > CC: Boris Ostrovsky <boris.ostrovsky@oracle.com> > > RFC, as I don't have easy access to a compiler which causes this to fail in > the first place. Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> with gcc 4.4.4
>>> On 05.01.17 at 19:01, <andrew.cooper3@citrix.com> wrote: > GCCs of at least 4.4 and earlier do not tollerate the initialisiation of the > $VENDOR_cpu_dev structures, because of c_ident becoming an anonymous union. > > Instead of using an anonymous union, reintepret c_ident[] in its CPUID form > just in get_cpu_vendor(). > > Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Reviewed-by: Jan Beulich <jbeulich@suse.com>
diff --git a/xen/arch/x86/cpu/common.c b/xen/arch/x86/cpu/common.c index d17a2ee..7d6d024 100644 --- a/xen/arch/x86/cpu/common.c +++ b/xen/arch/x86/cpu/common.c @@ -163,8 +163,11 @@ int get_cpu_vendor(uint32_t b, uint32_t c, uint32_t d, enum get_cpu_vendor mode) for (i = 0; i < X86_VENDOR_NUM; i++) { if (cpu_devs[i]) { - if (cpu_devs[i]->b == b && cpu_devs[i]->c == c && - cpu_devs[i]->d == d) { + struct { + uint32_t b, d, c; + } *ptr = (void *)cpu_devs[i]->c_ident; + + if (ptr->b == b && ptr->c == c && ptr->d == d) { if (mode == gcv_host) this_cpu = cpu_devs[i]; return i; diff --git a/xen/arch/x86/cpu/cpu.h b/xen/arch/x86/cpu/cpu.h index 5a7905c..3eeebe3 100644 --- a/xen/arch/x86/cpu/cpu.h +++ b/xen/arch/x86/cpu/cpu.h @@ -1,13 +1,7 @@ /* attempt to consolidate cpu attributes */ struct cpu_dev { char c_vendor[8]; - - union { - char c_ident[13]; - struct { - uint32_t b, d, c; - }; - }; + char c_ident[13]; void (*c_early_init)(struct cpuinfo_x86 *c); void (*c_init)(struct cpuinfo_x86 * c);
GCCs of at least 4.4 and earlier do not tollerate the initialisiation of the $VENDOR_cpu_dev structures, because of c_ident becoming an anonymous union. Instead of using an anonymous union, reintepret c_ident[] in its CPUID form just in get_cpu_vendor(). Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> --- CC: Jan Beulich <JBeulich@suse.com> CC: Boris Ostrovsky <boris.ostrovsky@oracle.com> RFC, as I don't have easy access to a compiler which causes this to fail in the first place. --- xen/arch/x86/cpu/common.c | 7 +++++-- xen/arch/x86/cpu/cpu.h | 8 +------- 2 files changed, 6 insertions(+), 9 deletions(-)