Re: [Xen-devel] [BUG] After upgrade to Xen 4.12.0 iommu=no-igfx

[Roman Shaposhnik <roman@xxxxxxxxxx>]

Sorry -- got a bit distracted yesterday. Attached is the log with only
your latest patch attached. Interestingly enough the box booted fine
without screen artifacts. So I guess we're getting closer...

Thanks for all the help!

Thanks,
Roman.

On Tue, Jul 30, 2019 at 2:21 AM Roger Pau Monné <roger.pau@xxxxxxxxxx> wrote:
>
> Ping?
>
> It would be very helpful for us in order to get this sorted out if you
> could answer the questions below and try the new debug patch :).
>
> On Fri, Jul 26, 2019 at 11:35:45AM +0200, Roger Pau Monné wrote:
> > On Thu, Jul 25, 2019 at 05:47:19PM -0700, Roman Shaposhnik wrote:
> > > Hi Roger!
> > >
> > > With your patch (and build as a debug build) Xen crashes on boot
> > > (which I guess was the point of your BUG_ON statement).
> >
> > Yes, that's very weird, seems like entries are not added to the iommu
> > page tables but I have no idea why, AFAICT this works fine on my
> > system.
> >
> > Do you have any patches on top of RELEASE-4.12.0?
> >
> > I have another patch with more verbose output, could you give it a
> > try? It's maybe going to be more chatty than the previous one.
> >
> > I'm sorry to keep you testing stuff, but since I cannot reproduce this
> > locally I have to rely on you to provide the debug output.
> >
> > Thanks, Roger.
> > ---8<---
> > diff --git a/xen/arch/x86/mm/p2m.c b/xen/arch/x86/mm/p2m.c
> > index b9bbb8f485..75f8359a99 100644
> > --- a/xen/arch/x86/mm/p2m.c
> > +++ b/xen/arch/x86/mm/p2m.c
> > @@ -1331,7 +1331,7 @@ int set_identity_p2m_entry(struct domain *d, unsigned 
> > long gfn_l,
> >
> >      if ( !paging_mode_translate(p2m->domain) )
> >      {
> > -        if ( !need_iommu_pt_sync(d) )
> > +        if ( !has_iommu_pt(d) )
> >              return 0;
> >          return iommu_legacy_map(d, _dfn(gfn_l), _mfn(gfn_l), PAGE_ORDER_4K,
> >                                  IOMMUF_readable | IOMMUF_writable);
> > @@ -1422,7 +1422,7 @@ int clear_identity_p2m_entry(struct domain *d, 
> > unsigned long gfn_l)
> >
> >      if ( !paging_mode_translate(d) )
> >      {
> > -        if ( !need_iommu_pt_sync(d) )
> > +        if ( !has_iommu_pt(d) )
> >              return 0;
> >          return iommu_legacy_unmap(d, _dfn(gfn_l), PAGE_ORDER_4K);
> >      }
> > diff --git a/xen/drivers/passthrough/iommu.c 
> > b/xen/drivers/passthrough/iommu.c
> > index 117b869b0c..214c5d515f 100644
> > --- a/xen/drivers/passthrough/iommu.c
> > +++ b/xen/drivers/passthrough/iommu.c
> > @@ -291,8 +291,18 @@ int iommu_map(struct domain *d, dfn_t dfn, mfn_t mfn,
> >      unsigned long i;
> >      int rc = 0;
> >
> > +if (dfn_x(dfn) >= 0x8d800 && dfn_x(dfn) < 0x90000 )
> > +{
> > +    printk("<RMRR> iommu_map %#lx\n", dfn_x(dfn));
> > +    process_pending_softirqs();
> > +}
> > +
> >      if ( !iommu_enabled || !hd->platform_ops )
> > +{
> > +    printk("iommu_enabled: %d platform_ops %p\n",
> > +           iommu_enabled, hd->platform_ops);
> >          return 0;
> > +}
> >
> >      ASSERT(IS_ALIGNED(dfn_x(dfn), (1ul << page_order)));
> >      ASSERT(IS_ALIGNED(mfn_x(mfn), (1ul << page_order)));
> > diff --git a/xen/drivers/passthrough/vtd/iommu.c 
> > b/xen/drivers/passthrough/vtd/iommu.c
> > index 50a0e25224..8c3fcb50ae 100644
> > --- a/xen/drivers/passthrough/vtd/iommu.c
> > +++ b/xen/drivers/passthrough/vtd/iommu.c
> > @@ -2009,12 +2009,33 @@ static int rmrr_identity_mapping(struct domain *d, 
> > bool_t map,
> >      if ( !map )
> >          return -ENOENT;
> >
> > +printk("<RMRR> mapping %#lx - %#lx\n", base_pfn, end_pfn);
> >      while ( base_pfn < end_pfn )
> >      {
> >          int err = set_identity_p2m_entry(d, base_pfn, p2m_access_rw, flag);
> > +        mfn_t mfn;
> > +        unsigned int f;
> >
> >          if ( err )
> >              return err;
> > +
> > +err = intel_iommu_lookup_page(d, _dfn(base_pfn), &mfn, &f);
> > +if ( err )
> > +{
> > +    printk("intel_iommu_lookup_page err: %d\n", err);
> > +    BUG();
> > +}
> > +if ( base_pfn != mfn_x(mfn) )
> > +{
> > +    printk("base_pfn: %#lx mfn: %#lx\n", base_pfn, mfn_x(mfn));
> > +    BUG();
> > +}
> > +if ( f != (IOMMUF_readable | IOMMUF_writable) )
> > +{
> > +    printk("flags: %#x\n", f);
> > +    BUG();
> > +}
> > +
> >          base_pfn++;
> >      }
> >
> > @@ -2263,6 +2284,7 @@ static void __hwdom_init setup_hwdom_rmrr(struct 
> > domain *d)
> >      u16 bdf;
> >      int ret, i;
> >
> > +printk("<RMRR> setting up regions\n");
> >      pcidevs_lock();
> >      for_each_rmrr_device ( rmrr, bdf, i )
> >      {
> >
> > _______________________________________________
> > Xen-devel mailing list
> > Xen-devel@xxxxxxxxxxxxxxxxxxxx
> > https://lists.xenproject.org/mailman/listinfo/xen-devel

Attachment: xen.txt
Description: Text document

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel