From: David Hildenbrand <david@xxxxxxxxxx> Subject: x86/xen: print a warning when HVMOP_get_mem_type fails HVMOP_get_mem_type is not expected to fail, "This call failing is indication of something going quite wrong and it would be good to know about this." [1] Let's add a pr_warn_once(). [1] https://lkml.kernel.org/r/3b935aa0-6d85-0bcd-100e-15098add3c4c@xxxxxxxxxx Link: https://lkml.kernel.org/r/20211005121430.30136-4-david@xxxxxxxxxx Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> Suggested-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx> Cc: Baoquan He <bhe@xxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Dave Young <dyoung@xxxxxxxxxx> Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Jason Wang <jasowang@xxxxxxxxxx> Cc: Juergen Gross <jgross@xxxxxxxx> Cc: "Michael S. Tsirkin" <mst@xxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: Mike Rapoport <rppt@xxxxxxxxxx> Cc: Oscar Salvador <osalvador@xxxxxxx> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@xxxxxxxxx> Cc: Stefano Stabellini <sstabellini@xxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Vivek Goyal <vgoyal@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/x86/xen/mmu_hvm.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/arch/x86/xen/mmu_hvm.c~x86-xen-print-a-warning-when-hvmop_get_mem_type-fails +++ a/arch/x86/xen/mmu_hvm.c @@ -22,8 +22,10 @@ static int xen_oldmem_pfn_is_ram(unsigne .pfn = pfn, }; - if (HYPERVISOR_hvm_op(HVMOP_get_mem_type, &a)) + if (HYPERVISOR_hvm_op(HVMOP_get_mem_type, &a)) { + pr_warn_once("Unexpected HVMOP_get_mem_type failure\n"); return -ENXIO; + } return a.mem_type != HVMMEM_mmio_dm; } #endif _