On Wed, Dec 23, 2020 at 02:24:12PM +0800, Zhenzhong Duan wrote: > check_iommu_entries() checks for cyclic dependency in iommu entries > and fixes the cyclic dependency by setting x->depend to NULL. But > this repairing isn't correct if q is in front of p, there will be > "EXECUTION ORDER INVALID!" report following. Fix it by NULLing > whichever in the front. > > The second issue is about the report of exectuion order reverse, > the order is reversed incorrectly in the report, fix it.
Heya! When you debugged this, did you by any chance save the serial logs and the debug logs to double-check it? Thanks! > > Signed-off-by: Zhenzhong Duan <zhenzhong.d...@gmail.com> > --- > arch/x86/kernel/pci-iommu_table.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/kernel/pci-iommu_table.c > b/arch/x86/kernel/pci-iommu_table.c > index 2e9006c..40c8249 100644 > --- a/arch/x86/kernel/pci-iommu_table.c > +++ b/arch/x86/kernel/pci-iommu_table.c > @@ -60,7 +60,10 @@ void __init check_iommu_entries(struct iommu_table_entry > *start, > printk(KERN_ERR "CYCLIC DEPENDENCY FOUND! %pS depends > on %pS and vice-versa. BREAKING IT.\n", > p->detect, q->detect); > /* Heavy handed way..*/ > - x->depend = NULL; > + if (p > q) > + q->depend = NULL; > + else > + p->depend = NULL; > } > } > > @@ -68,7 +71,7 @@ void __init check_iommu_entries(struct iommu_table_entry > *start, > q = find_dependents_of(p, finish, p); > if (q && q > p) { > printk(KERN_ERR "EXECUTION ORDER INVALID! %pS should be > called before %pS!\n", > - p->detect, q->detect); > + q->detect, p->detect); > } > } > } > -- > 1.8.3.1 >