Il Thu, Jun 14, 2007 at 11:26:29AM +0300, Avi Kivity ha scritto: > Luca Tettamanti wrote: > >With GOOD_APIC apic_read_around is a nop, while apic_write_around is a > >normal write. With !GOOD_APIC apic_write_around writes to the APIC reg > >using xchg. With !GOOD_APIC and this patch: > > > >--- include/asm-i386/apic.h~ 2007-04-26 05:08:32.000000000 +0200 > >+++ include/asm-i386/apic.h 2007-06-13 22:35:00.000000000 +0200 > >@@ -56,7 +56,8 @@ > > static __inline fastcall void native_apic_write_atomic(unsigned long reg, > > unsigned long v) > > { > >- xchg((volatile unsigned long *)(APIC_BASE+reg), v); > >+// xchg((volatile unsigned long *)(APIC_BASE+reg), v); > >+ *((volatile unsigned long *)(APIC_BASE+reg)) = v; > > } > > > > static __inline fastcall unsigned long native_apic_read(unsigned long reg) > > > >The kernel boots fine. > > > > Looking at the xchg emulation code, it seems fine, but clearly it > isn't.
Btw, I've put a printk in x86_emulate.c, where it prepares the operands for the xchg operations: all the write_atomic are hitting this point, so the write is lost somewhere in cmpxchg_emulated->write_emulated. Luca -- Il dottore mi ha detto di smettere di fare cene intime per quattro. A meno che non ci siamo altre tre persone. ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel