From: Paolo Bonzini <pbonzini@xxxxxxxxxx> commit 335e192a3fa415e1202c8b9ecdaaecd643f823cc upstream. These are useful in debugging shadow paging. Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx> [bwh: Backported to 4.9: - Keep using PT_PRESENT_MASK to test page write permission - Adjust context] Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/x86/kvm/mmu.c | 13 ++++----- arch/x86/kvm/mmutrace.h | 59 +++++++++++++++++++++++++++++++++++++++++++++ arch/x86/kvm/paging_tmpl.h | 2 + 3 files changed, 67 insertions(+), 7 deletions(-) --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -131,9 +131,6 @@ module_param(dbg, bool, 0644); #include <trace/events/kvm.h> -#define CREATE_TRACE_POINTS -#include "mmutrace.h" - #define SPTE_HOST_WRITEABLE (1ULL << PT_FIRST_AVAIL_BITS_SHIFT) #define SPTE_MMU_WRITEABLE (1ULL << (PT_FIRST_AVAIL_BITS_SHIFT + 1)) @@ -193,8 +190,12 @@ static u64 __read_mostly shadow_mmio_mas static u64 __read_mostly shadow_present_mask; static void mmu_spte_set(u64 *sptep, u64 spte); +static bool is_executable_pte(u64 spte); static void mmu_free_roots(struct kvm_vcpu *vcpu); +#define CREATE_TRACE_POINTS +#include "mmutrace.h" + void kvm_mmu_set_mmio_spte_mask(u64 mmio_mask) { shadow_mmio_mask = mmio_mask; @@ -2667,10 +2668,7 @@ static int mmu_set_spte(struct kvm_vcpu ret = RET_PF_EMULATE; pgprintk("%s: setting spte %llx\n", __func__, *sptep); - pgprintk("instantiating %s PTE (%s) at %llx (%llx) addr %p\n", - is_large_pte(*sptep)? "2MB" : "4kB", - *sptep & PT_PRESENT_MASK ?"RW":"R", gfn, - *sptep, sptep); + trace_kvm_mmu_set_spte(level, gfn, sptep); if (!was_rmapped && is_large_pte(*sptep)) ++vcpu->kvm->stat.lpages; @@ -2781,6 +2779,7 @@ static int __direct_map(struct kvm_vcpu if (!VALID_PAGE(vcpu->arch.mmu.root_hpa)) return RET_PF_RETRY; + trace_kvm_mmu_spte_requested(gpa, level, pfn); for_each_shadow_entry(vcpu, gpa, it) { base_gfn = gfn & ~(KVM_PAGES_PER_HPAGE(it.level) - 1); if (it.level == level) --- a/arch/x86/kvm/mmutrace.h +++ b/arch/x86/kvm/mmutrace.h @@ -322,6 +322,65 @@ TRACE_EVENT( __entry->kvm_gen == __entry->spte_gen ) ); + +TRACE_EVENT( + kvm_mmu_set_spte, + TP_PROTO(int level, gfn_t gfn, u64 *sptep), + TP_ARGS(level, gfn, sptep), + + TP_STRUCT__entry( + __field(u64, gfn) + __field(u64, spte) + __field(u64, sptep) + __field(u8, level) + /* These depend on page entry type, so compute them now. */ + __field(bool, r) + __field(bool, x) + __field(u8, u) + ), + + TP_fast_assign( + __entry->gfn = gfn; + __entry->spte = *sptep; + __entry->sptep = virt_to_phys(sptep); + __entry->level = level; + __entry->r = shadow_present_mask || (__entry->spte & PT_PRESENT_MASK); + __entry->x = is_executable_pte(__entry->spte); + __entry->u = shadow_user_mask ? !!(__entry->spte & shadow_user_mask) : -1; + ), + + TP_printk("gfn %llx spte %llx (%s%s%s%s) level %d at %llx", + __entry->gfn, __entry->spte, + __entry->r ? "r" : "-", + __entry->spte & PT_PRESENT_MASK ? "w" : "-", + __entry->x ? "x" : "-", + __entry->u == -1 ? "" : (__entry->u ? "u" : "-"), + __entry->level, __entry->sptep + ) +); + +TRACE_EVENT( + kvm_mmu_spte_requested, + TP_PROTO(gpa_t addr, int level, kvm_pfn_t pfn), + TP_ARGS(addr, level, pfn), + + TP_STRUCT__entry( + __field(u64, gfn) + __field(u64, pfn) + __field(u8, level) + ), + + TP_fast_assign( + __entry->gfn = addr >> PAGE_SHIFT; + __entry->pfn = pfn | (__entry->gfn & (KVM_PAGES_PER_HPAGE(level) - 1)); + __entry->level = level; + ), + + TP_printk("gfn %llx pfn %llx level %d", + __entry->gfn, __entry->pfn, __entry->level + ) +); + #endif /* _TRACE_KVMMMU_H */ #undef TRACE_INCLUDE_PATH --- a/arch/x86/kvm/paging_tmpl.h +++ b/arch/x86/kvm/paging_tmpl.h @@ -626,6 +626,8 @@ static int FNAME(fetch)(struct kvm_vcpu base_gfn = gw->gfn; + trace_kvm_mmu_spte_requested(addr, gw->level, pfn); + for (; shadow_walk_okay(&it); shadow_walk_next(&it)) { clear_sp_write_flooding_count(it.sptep); base_gfn = gw->gfn & ~(KVM_PAGES_PER_HPAGE(it.level) - 1);