powerpc fixes for 4.1
- Fix for mm_dec_nr_pmds() from Scott. - Fixes for oopses seen with KVM + THP from Aneesh. - Build fixes from Aneesh & Shreyas. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAABAgAGBQJVOsk5AAoJEFHr6jzI4aWACWMP/3EaNoeA1g8VbZWZEdRaoLvX W7D08DI3Dt8HLxyn2JR08jYZF0gr68XrF6OiscVVki7wVXT8fbH4jSNmBkbzNH95 d9taScJyR1CUavkhsXivnR1qEE1Fi2KA2OW9RaNfoSt1MVtdsvOK6xXklUGksuJQ XygzyrRr4Dj82kuMUAMO0YDMvknMlzi3a8dzyrWZBXBZOOTWavGB6bQKtCTaOQ99 3OFGLQ10uY7lmdHDi0t0tQ99FuYfLiJpg5fTLoUni4J5tFp8JlZ+x0Gwc0apN0cy Ym8EO6++qWDv8FXvYEPfVUEjbF1fyPiawUgpkMnyvXgd8K5G85SIrtkGW0Ml+6sX GfJH8w9hpDbF5EnWlC9bn/jT7sHBHFdrxZuQUc0L4M2OtM73R2a0Xr3b7ZxFCD1q 7RpYu8MKKcyvaIXNg7VBJjj8zL+WmUJKF6J5uX5bGU2xH0khmp0vTknyyjbwrlcF uHidv5ZhMt3aAI70v14jA5BTEmLyOYRu58Ei6cT/VT/DjdbpEApdK8BMAvKSEeib +hzh6oDFT92AM0tbg15bNmqGbGfgqtVKe4GDS2QyGaHGAFOGs1nPuSa9se1xYDcM CCtRyABwpzJsrCfwra2fsTU6FxlatK4ONViyWFBXa6mEjBNSZ4XmyZvdWUqlwpSC F5jNGppm5Ama6xxcLphA =6yQx -----END PGP SIGNATURE----- Merge tag 'powerpc-4.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux Pull powerpc fixes from Michael Ellerman: - fix for mm_dec_nr_pmds() from Scott. - fixes for oopses seen with KVM + THP from Aneesh. - build fixes from Aneesh & Shreyas. * tag 'powerpc-4.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: powerpc/mm: Fix build error with CONFIG_PPC_TRANSACTIONAL_MEM disabled powerpc/kvm: Fix ppc64_defconfig + PPC_POWERNV=n build error powerpc/mm/thp: Return pte address if we find trans_splitting. powerpc/mm/thp: Make page table walk safe against thp split/collapse KVM: PPC: Remove page table walk helpers KVM: PPC: Use READ_ONCE when dereferencing pte_t pointer powerpc/hugetlb: Call mm_dec_nr_pmds() in hugetlb_free_pmd_range()
This commit is contained in:
Linus Torvalds
Коммит
63905bba5b
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@ -295,16 +295,17 @@ static inline int hpte_cache_flags_ok(unsigned long ptel, unsigned long io_type)
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/*
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* If it's present and writable, atomically set dirty and referenced bits and
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* return the PTE, otherwise return 0. If we find a transparent hugepage
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* and if it is marked splitting we return 0;
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* return the PTE, otherwise return 0.
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*/
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static inline pte_t kvmppc_read_update_linux_pte(pte_t *ptep, int writing,
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unsigned int hugepage)
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static inline pte_t kvmppc_read_update_linux_pte(pte_t *ptep, int writing)
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{
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pte_t old_pte, new_pte = __pte(0);
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while (1) {
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old_pte = *ptep;
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/*
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* Make sure we don't reload from ptep
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*/
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old_pte = READ_ONCE(*ptep);
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/*
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* wait until _PAGE_BUSY is clear then set it atomically
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*/
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@ -312,12 +313,6 @@ static inline pte_t kvmppc_read_update_linux_pte(pte_t *ptep, int writing,
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cpu_relax();
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continue;
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}
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#ifdef CONFIG_TRANSPARENT_HUGEPAGE
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/* If hugepage and is trans splitting return None */
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if (unlikely(hugepage &&
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pmd_trans_splitting(pte_pmd(old_pte))))
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return __pte(0);
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#endif
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/* If pte is not present return None */
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if (unlikely(!(pte_val(old_pte) & _PAGE_PRESENT)))
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return __pte(0);
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@ -247,28 +247,16 @@ extern int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned long addr,
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#define pmd_large(pmd) 0
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#define has_transparent_hugepage() 0
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#endif
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pte_t *find_linux_pte_or_hugepte(pgd_t *pgdir, unsigned long ea,
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pte_t *__find_linux_pte_or_hugepte(pgd_t *pgdir, unsigned long ea,
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unsigned *shift);
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static inline pte_t *lookup_linux_ptep(pgd_t *pgdir, unsigned long hva,
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unsigned long *pte_sizep)
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static inline pte_t *find_linux_pte_or_hugepte(pgd_t *pgdir, unsigned long ea,
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unsigned *shift)
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{
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pte_t *ptep;
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unsigned long ps = *pte_sizep;
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unsigned int shift;
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ptep = find_linux_pte_or_hugepte(pgdir, hva, &shift);
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if (!ptep)
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return NULL;
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if (shift)
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*pte_sizep = 1ul << shift;
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else
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*pte_sizep = PAGE_SIZE;
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if (ps > *pte_sizep)
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return NULL;
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return ptep;
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if (!arch_irqs_disabled()) {
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pr_info("%s called with irq enabled\n", __func__);
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dump_stack();
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}
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return __find_linux_pte_or_hugepte(pgdir, ea, shift);
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}
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#endif /* __ASSEMBLY__ */
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@ -334,9 +334,11 @@ static inline unsigned long eeh_token_to_phys(unsigned long token)
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int hugepage_shift;
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/*
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* We won't find hugepages here, iomem
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* We won't find hugepages here(this is iomem). Hence we are not
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* worried about _PAGE_SPLITTING/collapse. Also we will not hit
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* page table free, because of init_mm.
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*/
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ptep = find_linux_pte_or_hugepte(init_mm.pgd, token, &hugepage_shift);
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ptep = __find_linux_pte_or_hugepte(init_mm.pgd, token, &hugepage_shift);
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if (!ptep)
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return token;
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WARN_ON(hugepage_shift);
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@ -71,15 +71,15 @@ struct iowa_bus *iowa_mem_find_bus(const PCI_IO_ADDR addr)
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vaddr = (unsigned long)PCI_FIX_ADDR(addr);
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if (vaddr < PHB_IO_BASE || vaddr >= PHB_IO_END)
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return NULL;
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ptep = find_linux_pte_or_hugepte(init_mm.pgd, vaddr,
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/*
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* We won't find huge pages here (iomem). Also can't hit
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* a page table free due to init_mm
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*/
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ptep = __find_linux_pte_or_hugepte(init_mm.pgd, vaddr,
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&hugepage_shift);
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if (ptep == NULL)
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paddr = 0;
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else {
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/*
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* we don't have hugepages backing iomem
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*/
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WARN_ON(hugepage_shift);
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paddr = pte_pfn(*ptep) << PAGE_SHIFT;
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}
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@ -75,7 +75,7 @@ config KVM_BOOK3S_64
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config KVM_BOOK3S_64_HV
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tristate "KVM support for POWER7 and PPC970 using hypervisor mode in host"
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depends on KVM_BOOK3S_64
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depends on KVM_BOOK3S_64 && PPC_POWERNV
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select KVM_BOOK3S_HV_POSSIBLE
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select MMU_NOTIFIER
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select CMA
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@ -535,23 +535,21 @@ int kvmppc_book3s_hv_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu,
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}
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/* if the guest wants write access, see if that is OK */
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if (!writing && hpte_is_writable(r)) {
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unsigned int hugepage_shift;
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pte_t *ptep, pte;
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unsigned long flags;
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/*
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* We need to protect against page table destruction
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* while looking up and updating the pte.
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* hugepage split and collapse.
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*/
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rcu_read_lock_sched();
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local_irq_save(flags);
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ptep = find_linux_pte_or_hugepte(current->mm->pgd,
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hva, &hugepage_shift);
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hva, NULL);
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if (ptep) {
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pte = kvmppc_read_update_linux_pte(ptep, 1,
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hugepage_shift);
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pte = kvmppc_read_update_linux_pte(ptep, 1);
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if (pte_write(pte))
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write_ok = 1;
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}
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rcu_read_unlock_sched();
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local_irq_restore(flags);
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}
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}
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@ -26,11 +26,14 @@ static void *real_vmalloc_addr(void *x)
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{
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unsigned long addr = (unsigned long) x;
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pte_t *p;
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p = find_linux_pte_or_hugepte(swapper_pg_dir, addr, NULL);
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/*
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* assume we don't have huge pages in vmalloc space...
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* So don't worry about THP collapse/split. Called
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* Only in realmode, hence won't need irq_save/restore.
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*/
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p = __find_linux_pte_or_hugepte(swapper_pg_dir, addr, NULL);
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if (!p || !pte_present(*p))
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return NULL;
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/* assume we don't have huge pages in vmalloc space... */
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addr = (pte_pfn(*p) << PAGE_SHIFT) | (addr & ~PAGE_MASK);
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return __va(addr);
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}
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@ -131,25 +134,6 @@ static void remove_revmap_chain(struct kvm *kvm, long pte_index,
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unlock_rmap(rmap);
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}
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static pte_t lookup_linux_pte_and_update(pgd_t *pgdir, unsigned long hva,
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int writing, unsigned long *pte_sizep)
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{
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pte_t *ptep;
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unsigned long ps = *pte_sizep;
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unsigned int hugepage_shift;
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ptep = find_linux_pte_or_hugepte(pgdir, hva, &hugepage_shift);
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if (!ptep)
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return __pte(0);
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if (hugepage_shift)
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*pte_sizep = 1ul << hugepage_shift;
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else
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*pte_sizep = PAGE_SIZE;
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if (ps > *pte_sizep)
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return __pte(0);
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return kvmppc_read_update_linux_pte(ptep, writing, hugepage_shift);
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}
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long kvmppc_do_h_enter(struct kvm *kvm, unsigned long flags,
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long pte_index, unsigned long pteh, unsigned long ptel,
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pgd_t *pgdir, bool realmode, unsigned long *pte_idx_ret)
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@ -160,13 +144,13 @@ long kvmppc_do_h_enter(struct kvm *kvm, unsigned long flags,
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struct revmap_entry *rev;
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unsigned long g_ptel;
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struct kvm_memory_slot *memslot;
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unsigned long pte_size;
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unsigned hpage_shift;
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unsigned long is_io;
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unsigned long *rmap;
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pte_t pte;
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pte_t *ptep;
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unsigned int writing;
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unsigned long mmu_seq;
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unsigned long rcbits;
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unsigned long rcbits, irq_flags = 0;
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psize = hpte_page_size(pteh, ptel);
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if (!psize)
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@ -202,22 +186,46 @@ long kvmppc_do_h_enter(struct kvm *kvm, unsigned long flags,
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/* Translate to host virtual address */
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hva = __gfn_to_hva_memslot(memslot, gfn);
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/* Look up the Linux PTE for the backing page */
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pte_size = psize;
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pte = lookup_linux_pte_and_update(pgdir, hva, writing, &pte_size);
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if (pte_present(pte) && !pte_protnone(pte)) {
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if (writing && !pte_write(pte))
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/* make the actual HPTE be read-only */
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ptel = hpte_make_readonly(ptel);
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is_io = hpte_cache_bits(pte_val(pte));
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pa = pte_pfn(pte) << PAGE_SHIFT;
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pa |= hva & (pte_size - 1);
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pa |= gpa & ~PAGE_MASK;
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/*
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* If we had a page table table change after lookup, we would
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* retry via mmu_notifier_retry.
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*/
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if (realmode)
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ptep = __find_linux_pte_or_hugepte(pgdir, hva, &hpage_shift);
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else {
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local_irq_save(irq_flags);
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ptep = find_linux_pte_or_hugepte(pgdir, hva, &hpage_shift);
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}
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if (ptep) {
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pte_t pte;
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unsigned int host_pte_size;
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if (pte_size < psize)
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return H_PARAMETER;
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if (hpage_shift)
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host_pte_size = 1ul << hpage_shift;
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else
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host_pte_size = PAGE_SIZE;
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/*
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* We should always find the guest page size
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* to <= host page size, if host is using hugepage
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*/
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if (host_pte_size < psize) {
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if (!realmode)
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local_irq_restore(flags);
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return H_PARAMETER;
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}
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pte = kvmppc_read_update_linux_pte(ptep, writing);
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if (pte_present(pte) && !pte_protnone(pte)) {
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if (writing && !pte_write(pte))
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/* make the actual HPTE be read-only */
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ptel = hpte_make_readonly(ptel);
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is_io = hpte_cache_bits(pte_val(pte));
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pa = pte_pfn(pte) << PAGE_SHIFT;
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pa |= hva & (host_pte_size - 1);
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pa |= gpa & ~PAGE_MASK;
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}
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}
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if (!realmode)
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local_irq_restore(irq_flags);
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ptel &= ~(HPTE_R_PP0 - psize);
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ptel |= pa;
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@ -338,6 +338,7 @@ static inline int kvmppc_e500_shadow_map(struct kvmppc_vcpu_e500 *vcpu_e500,
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pte_t *ptep;
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unsigned int wimg = 0;
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pgd_t *pgdir;
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unsigned long flags;
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/* used to check for invalidations in progress */
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mmu_seq = kvm->mmu_notifier_seq;
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@ -468,15 +469,28 @@ static inline int kvmppc_e500_shadow_map(struct kvmppc_vcpu_e500 *vcpu_e500,
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pgdir = vcpu_e500->vcpu.arch.pgdir;
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ptep = lookup_linux_ptep(pgdir, hva, &tsize_pages);
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if (pte_present(*ptep))
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wimg = (*ptep >> PTE_WIMGE_SHIFT) & MAS2_WIMGE_MASK;
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else {
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if (printk_ratelimit())
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pr_err("%s: pte not present: gfn %lx, pfn %lx\n",
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__func__, (long)gfn, pfn);
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ret = -EINVAL;
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goto out;
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/*
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* We are just looking at the wimg bits, so we don't
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* care much about the trans splitting bit.
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* We are holding kvm->mmu_lock so a notifier invalidate
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* can't run hence pfn won't change.
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*/
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local_irq_save(flags);
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ptep = find_linux_pte_or_hugepte(pgdir, hva, NULL);
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if (ptep) {
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pte_t pte = READ_ONCE(*ptep);
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if (pte_present(pte)) {
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wimg = (pte_val(pte) >> PTE_WIMGE_SHIFT) &
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MAS2_WIMGE_MASK;
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local_irq_restore(flags);
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} else {
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local_irq_restore(flags);
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pr_err_ratelimited("%s: pte not present: gfn %lx,pfn %lx\n",
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__func__, (long)gfn, pfn);
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ret = -EINVAL;
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goto out;
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}
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}
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kvmppc_e500_ref_setup(ref, gtlbe, pfn, wimg);
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@ -1066,7 +1066,7 @@ int hash_page_mm(struct mm_struct *mm, unsigned long ea,
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#endif /* CONFIG_PPC_64K_PAGES */
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/* Get PTE and page size from page tables */
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ptep = find_linux_pte_or_hugepte(pgdir, ea, &hugeshift);
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ptep = __find_linux_pte_or_hugepte(pgdir, ea, &hugeshift);
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if (ptep == NULL || !pte_present(*ptep)) {
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DBG_LOW(" no PTE !\n");
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rc = 1;
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@ -1394,6 +1394,7 @@ tm_abort:
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tm_abort(TM_CAUSE_TLBI);
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}
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#endif
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return;
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}
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#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
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|
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|
|
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@ -109,7 +109,7 @@ int pgd_huge(pgd_t pgd)
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pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
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{
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/* Only called for hugetlbfs pages, hence can ignore THP */
|
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return find_linux_pte_or_hugepte(mm->pgd, addr, NULL);
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return __find_linux_pte_or_hugepte(mm->pgd, addr, NULL);
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}
|
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|
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static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp,
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@ -581,6 +581,7 @@ static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud,
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pmd = pmd_offset(pud, start);
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pud_clear(pud);
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pmd_free_tlb(tlb, pmd, start);
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mm_dec_nr_pmds(tlb->mm);
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}
|
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|
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static void hugetlb_free_pud_range(struct mmu_gather *tlb, pgd_t *pgd,
|
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|
|
@ -681,28 +682,35 @@ void hugetlb_free_pgd_range(struct mmu_gather *tlb,
|
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} while (addr = next, addr != end);
|
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}
|
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|
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/*
|
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* We are holding mmap_sem, so a parallel huge page collapse cannot run.
|
||||
* To prevent hugepage split, disable irq.
|
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*/
|
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struct page *
|
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follow_huge_addr(struct mm_struct *mm, unsigned long address, int write)
|
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{
|
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pte_t *ptep;
|
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struct page *page;
|
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unsigned shift;
|
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unsigned long mask;
|
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unsigned long mask, flags;
|
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/*
|
||||
* Transparent hugepages are handled by generic code. We can skip them
|
||||
* here.
|
||||
*/
|
||||
local_irq_save(flags);
|
||||
ptep = find_linux_pte_or_hugepte(mm->pgd, address, &shift);
|
||||
|
||||
/* Verify it is a huge page else bail. */
|
||||
if (!ptep || !shift || pmd_trans_huge(*(pmd_t *)ptep))
|
||||
if (!ptep || !shift || pmd_trans_huge(*(pmd_t *)ptep)) {
|
||||
local_irq_restore(flags);
|
||||
return ERR_PTR(-EINVAL);
|
||||
|
||||
}
|
||||
mask = (1UL << shift) - 1;
|
||||
page = pte_page(*ptep);
|
||||
if (page)
|
||||
page += (address & mask) / PAGE_SIZE;
|
||||
|
||||
local_irq_restore(flags);
|
||||
return page;
|
||||
}
|
||||
|
||||
|
|
@ -949,9 +957,12 @@ void flush_dcache_icache_hugepage(struct page *page)
|
|||
*
|
||||
* So long as we atomically load page table pointers we are safe against teardown,
|
||||
* we can follow the address down to the the page and take a ref on it.
|
||||
* This function need to be called with interrupts disabled. We use this variant
|
||||
* when we have MSR[EE] = 0 but the paca->soft_enabled = 1
|
||||
*/
|
||||
|
||||
pte_t *find_linux_pte_or_hugepte(pgd_t *pgdir, unsigned long ea, unsigned *shift)
|
||||
pte_t *__find_linux_pte_or_hugepte(pgd_t *pgdir, unsigned long ea,
|
||||
unsigned *shift)
|
||||
{
|
||||
pgd_t pgd, *pgdp;
|
||||
pud_t pud, *pudp;
|
||||
|
|
@ -1003,12 +1014,11 @@ pte_t *find_linux_pte_or_hugepte(pgd_t *pgdir, unsigned long ea, unsigned *shift
|
|||
* A hugepage collapse is captured by pmd_none, because
|
||||
* it mark the pmd none and do a hpte invalidate.
|
||||
*
|
||||
* A hugepage split is captured by pmd_trans_splitting
|
||||
* because we mark the pmd trans splitting and do a
|
||||
* hpte invalidate
|
||||
*
|
||||
* We don't worry about pmd_trans_splitting here, The
|
||||
* caller if it needs to handle the splitting case
|
||||
* should check for that.
|
||||
*/
|
||||
if (pmd_none(pmd) || pmd_trans_splitting(pmd))
|
||||
if (pmd_none(pmd))
|
||||
return NULL;
|
||||
|
||||
if (pmd_huge(pmd) || pmd_large(pmd)) {
|
||||
|
|
@ -1030,7 +1040,7 @@ out:
|
|||
*shift = pdshift;
|
||||
return ret_pte;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(find_linux_pte_or_hugepte);
|
||||
EXPORT_SYMBOL_GPL(__find_linux_pte_or_hugepte);
|
||||
|
||||
int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned long addr,
|
||||
unsigned long end, int write, struct page **pages, int *nr)
|
||||
|
|
|
|||
|
|
@ -111,41 +111,45 @@ perf_callchain_kernel(struct perf_callchain_entry *entry, struct pt_regs *regs)
|
|||
* interrupt context, so if the access faults, we read the page tables
|
||||
* to find which page (if any) is mapped and access it directly.
|
||||
*/
|
||||
static int read_user_stack_slow(void __user *ptr, void *ret, int nb)
|
||||
static int read_user_stack_slow(void __user *ptr, void *buf, int nb)
|
||||
{
|
||||
int ret = -EFAULT;
|
||||
pgd_t *pgdir;
|
||||
pte_t *ptep, pte;
|
||||
unsigned shift;
|
||||
unsigned long addr = (unsigned long) ptr;
|
||||
unsigned long offset;
|
||||
unsigned long pfn;
|
||||
unsigned long pfn, flags;
|
||||
void *kaddr;
|
||||
|
||||
pgdir = current->mm->pgd;
|
||||
if (!pgdir)
|
||||
return -EFAULT;
|
||||
|
||||
local_irq_save(flags);
|
||||
ptep = find_linux_pte_or_hugepte(pgdir, addr, &shift);
|
||||
if (!ptep)
|
||||
goto err_out;
|
||||
if (!shift)
|
||||
shift = PAGE_SHIFT;
|
||||
|
||||
/* align address to page boundary */
|
||||
offset = addr & ((1UL << shift) - 1);
|
||||
addr -= offset;
|
||||
|
||||
if (ptep == NULL)
|
||||
return -EFAULT;
|
||||
pte = *ptep;
|
||||
pte = READ_ONCE(*ptep);
|
||||
if (!pte_present(pte) || !(pte_val(pte) & _PAGE_USER))
|
||||
return -EFAULT;
|
||||
goto err_out;
|
||||
pfn = pte_pfn(pte);
|
||||
if (!page_is_ram(pfn))
|
||||
return -EFAULT;
|
||||
goto err_out;
|
||||
|
||||
/* no highmem to worry about here */
|
||||
kaddr = pfn_to_kaddr(pfn);
|
||||
memcpy(ret, kaddr + offset, nb);
|
||||
return 0;
|
||||
memcpy(buf, kaddr + offset, nb);
|
||||
ret = 0;
|
||||
err_out:
|
||||
local_irq_restore(flags);
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int read_user_stack_64(unsigned long __user *ptr, unsigned long *ret)
|
||||
|
|
|
|||
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Ссылка в новой задаче