> It looks obvious (based upon looking at an older version, where it
> was simply an error if the buffer was not aligned), the
>
> wrmsr(MSR_BIOS_UPDT_TRIG, (uintptr_t)(sc->sc_blob) + 48);
>
> should be using uh (which is the same value as sc->sc_blob if that
> was aligned satisfactorily on entry) rather than sc->sc_blob.
>
> The code as it is is clearly broken, I'm not sure why there's even any
> discussion about this.
nicely spotted. i don't think anyone else noticed.
> Cease the silly discussion, and just fix it
i think it's hard to test, thus hard to commit.
how about this:
Index: cpu_ucode_intel.c
===================================================================
RCS file: /cvsroot/src/sys/arch/x86/x86/cpu_ucode_intel.c,v
retrieving revision 1.8
diff -p -u -r1.8 cpu_ucode_intel.c
--- cpu_ucode_intel.c 12 May 2015 00:00:35 -0000 1.8
+++ cpu_ucode_intel.c 4 Oct 2015 00:48:45 -0000
@@ -110,7 +110,7 @@ cpu_ucode_intel_apply(struct cpu_ucode_s
{
uint32_t ucodetarget, oucodeversion, nucodeversion;
int platformid;
- struct intel1_ucode_header *uh;
+ struct intel1_ucode_header *uh, *uha;
size_t newbufsize = 0;
int rv = 0;
@@ -126,12 +126,12 @@ cpu_ucode_intel_apply(struct cpu_ucode_s
if ((uintptr_t)(sc->sc_blob) & 15) {
/* Make the buffer 16 byte aligned */
newbufsize = sc->sc_blobsize + 15;
- uh = kmem_alloc(newbufsize, KM_SLEEP);
- if (uh == NULL) {
+ uha = kmem_alloc(newbufsize, KM_SLEEP);
+ if (uha == NULL) {
printf("%s: memory allocation failed\n", __func__);
return EINVAL;
}
- uh = (struct intel1_ucode_header *)roundup2((uintptr_t)uh, 16);
+ uh = (struct intel1_ucode_header *)roundup2((uintptr_t)uha, 16);
/* Copy to the new area */
memcpy(uh, sc->sc_blob, sc->sc_blobsize);
}
@@ -144,7 +144,7 @@ cpu_ucode_intel_apply(struct cpu_ucode_s
rv = EEXIST; /* ??? */
goto out;
}
- wrmsr(MSR_BIOS_UPDT_TRIG, (uintptr_t)(sc->sc_blob) + 48);
+ wrmsr(MSR_BIOS_UPDT_TRIG, (uintptr_t)uh + 48);
intel_getcurrentucode(&nucodeversion, &platformid);
kpreempt_enable();
@@ -158,7 +158,7 @@ cpu_ucode_intel_apply(struct cpu_ucode_s
oucodeversion, nucodeversion);
out:
if (newbufsize != 0)
- kmem_free(uh, newbufsize);
+ kmem_free(uha, newbufsize);
return rv;
}
#endif /* ! XEN */
