ports/emulators/kqemu-kmod-devel/files/patch-tssworkaround
Juergen Lock 7db429fd44 - Call the tss fixup code before entering the monitor instead of after.
(This fixes the problems that one user saw which I couldn't reproduce.)
- Bump PORTREVISION
2008-06-05 18:49:12 +00:00

112 lines
3 KiB
Text

Index: kqemu-freebsd.c
@@ -38,6 +38,14 @@
#else
#include <machine/npx.h>
#endif
+#ifdef __x86_64__
+#include <sys/smp.h>
+#include <sys/pcpu.h>
+#include <machine/pcb.h>
+#include <machine/specialreg.h>
+#include <machine/segments.h>
+#include <machine/tss.h>
+#endif
#include "kqemu-kernel.h"
@@ -248,6 +256,57 @@
va_end(ap);
}
+#ifdef __x86_64__
+int kqemu_cpu0gdtfixed;
+int kqemu_gdts_used;
+struct user_segment_descriptor *kqemu_gdts;
+struct region_descriptor kqemu_r_newgdt;
+extern struct pcpu __pcpu[];
+
+/* called with interrupts disabled */
+void CDECL kqemu_tss_fixup(unsigned long kerngdtbase)
+{
+ int gsel_tss = GSEL(GPROC0_SEL, SEL_KPL);
+ unsigned cpuid = PCPU_GET(cpuid);
+ struct user_segment_descriptor *newgdt = gdt;
+
+ if (mp_ncpus <= 1 || kerngdtbase != (unsigned long)gdt)
+ /* UP host or gdt already moved, nothing to do */
+ return;
+ if (cpuid) {
+ /* move gdts of all but first cpu */
+ if (!kqemu_gdts)
+ /*
+ * XXX gdt is allocated as
+ * struct user_segment_descriptor gdt[NGDT * MAXCPU];
+ * so it has room for the moved copies; need to allocate at
+ * kldload (and only free if kqemu_gdts_used is zero) should this
+ * change in the future
+ */
+ kqemu_gdts = &gdt[NGDT];
+ ++kqemu_gdts_used;
+ newgdt = &kqemu_gdts[NGDT * (cpuid - 1)];
+ bcopy(gdt, newgdt, NGDT * sizeof(gdt[0]));
+ kqemu_r_newgdt.rd_limit = NGDT * sizeof(gdt[0]) - 1;
+ kqemu_r_newgdt.rd_base = (long) newgdt;
+ } else {
+ if (kqemu_cpu0gdtfixed)
+ return;
+ ++kqemu_cpu0gdtfixed;
+ }
+ gdt_segs[GPROC0_SEL].ssd_base = (long) &common_tss[cpuid];
+ ssdtosyssd(&gdt_segs[GPROC0_SEL],
+ (struct system_segment_descriptor *)&newgdt[GPROC0_SEL]);
+ if (cpuid) {
+ lgdt(&kqemu_r_newgdt);
+ wrmsr(MSR_GSBASE, (u_int64_t)&__pcpu[cpuid]);
+ wrmsr(MSR_KGSBASE, curthread->td_pcb->pcb_gsbase);
+ wrmsr(MSR_FSBASE, curthread->td_pcb->pcb_fsbase);
+ }
+ ltr(gsel_tss);
+}
+#endif
+
struct kqemu_instance {
#if __FreeBSD_version >= 500000
TAILQ_ENTRY(kqemu_instance) kqemu_ent;
Index: common/kernel.c
@@ -1025,6 +1025,9 @@
#ifdef __x86_64__
uint16_t saved_ds, saved_es;
unsigned long fs_base, gs_base;
+#ifdef __FreeBSD__
+ struct kqemu_global_state *g = s->global_state;
+#endif
#endif
#ifdef PROFILE
@@ -1096,6 +1099,14 @@
apic_nmi_mask = apic_save_and_disable_nmi(s);
}
+#ifdef __FreeBSD__
+#ifdef __x86_64__
+ spin_lock(&g->lock);
+ asm volatile ("sgdt %0" : : "m" (s->kernel_gdt));
+ kqemu_tss_fixup(s->kernel_gdt.base);
+ spin_unlock(&g->lock);
+#endif
+#endif
/* load breakpoint registers and avoid setting them if in the
monitor address space. We suppose that no breakpoints are
set by the host OS for this process */
Index: kqemu-kernel.h
@@ -48,4 +48,10 @@
void CDECL kqemu_log(const char *fmt, ...);
+#ifdef __FreeBSD__
+#ifdef __x86_64__
+void CDECL kqemu_tss_fixup(unsigned long kerngdtbase);
+#endif
+#endif
+
#endif /* KQEMU_KERNEL_H */