[kernel/f22] arm64-revert-tlb-rcu_table_free.patch: revert 5e5f6dc1
Kyle McMartin
kyle at fedoraproject.org
Fri Mar 13 16:39:45 UTC 2015
commit 088b1f27a9ac1b6df3180ed4d132d4fd280862fe
Author: Kyle McMartin <kmcmarti at redhat.com>
Date: Fri Mar 13 12:38:27 2015 -0400
arm64-revert-tlb-rcu_table_free.patch: revert 5e5f6dc1
which causes lockups on arm64 machines.
arm64-revert-tlb-rcu_table_free.patch | 436 ++++++++++++++++++++++++++++++++++
kernel.spec | 7 +
2 files changed, 443 insertions(+)
---
diff --git a/arm64-revert-tlb-rcu_table_free.patch b/arm64-revert-tlb-rcu_table_free.patch
new file mode 100644
index 0000000..5291fa5
--- /dev/null
+++ b/arm64-revert-tlb-rcu_table_free.patch
@@ -0,0 +1,436 @@
+diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
+index 1b8e973..31042fe 100644
+--- a/arch/arm64/Kconfig
++++ b/arch/arm64/Kconfig
+@@ -65,7 +65,6 @@ config ARM64
+ select HAVE_PERF_EVENTS
+ select HAVE_PERF_REGS
+ select HAVE_PERF_USER_STACK_DUMP
+- select HAVE_RCU_TABLE_FREE
+ select HAVE_SYSCALL_TRACEPOINTS
+ select IRQ_DOMAIN
+ select MODULES_USE_ELF_RELA
+@@ -119,9 +118,6 @@ config GENERIC_CALIBRATE_DELAY
+ config ZONE_DMA
+ def_bool y
+
+-config HAVE_GENERIC_RCU_GUP
+- def_bool y
+-
+ config ARCH_DMA_ADDR_T_64BIT
+ def_bool y
+
+diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
+index 800ec0e..e2e79ac 100644
+--- a/arch/arm64/include/asm/pgtable.h
++++ b/arch/arm64/include/asm/pgtable.h
+@@ -243,16 +243,6 @@ static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
+
+ #define __HAVE_ARCH_PTE_SPECIAL
+
+-static inline pte_t pud_pte(pud_t pud)
+-{
+- return __pte(pud_val(pud));
+-}
+-
+-static inline pmd_t pud_pmd(pud_t pud)
+-{
+- return __pmd(pud_val(pud));
+-}
+-
+ static inline pte_t pmd_pte(pmd_t pmd)
+ {
+ return __pte(pmd_val(pmd));
+@@ -275,13 +265,7 @@ static inline pgprot_t mk_sect_prot(pgprot_t prot)
+ #ifdef CONFIG_TRANSPARENT_HUGEPAGE
+ #define pmd_trans_huge(pmd) (pmd_val(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT))
+ #define pmd_trans_splitting(pmd) pte_special(pmd_pte(pmd))
+-#ifdef CONFIG_HAVE_RCU_TABLE_FREE
+-#define __HAVE_ARCH_PMDP_SPLITTING_FLUSH
+-struct vm_area_struct;
+-void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address,
+- pmd_t *pmdp);
+-#endif /* CONFIG_HAVE_RCU_TABLE_FREE */
+-#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
++#endif
+
+ #define pmd_dirty(pmd) pte_dirty(pmd_pte(pmd))
+ #define pmd_young(pmd) pte_young(pmd_pte(pmd))
+@@ -302,7 +286,7 @@ void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address,
+ #define pfn_pmd(pfn,prot) (__pmd(((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot)))
+ #define mk_pmd(page,prot) pfn_pmd(page_to_pfn(page),prot)
+
+-#define pud_write(pud) pte_write(pud_pte(pud))
++#define pmd_page(pmd) pfn_to_page(__phys_to_pfn(pmd_val(pmd) & PHYS_MASK))
+ #define pud_pfn(pud) (((pud_val(pud) & PUD_MASK) & PHYS_MASK) >> PAGE_SHIFT)
+
+ #define set_pmd_at(mm, addr, pmdp, pmd) set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd))
+@@ -407,8 +391,6 @@ static inline pmd_t *pmd_offset(pud_t *pud, unsigned long addr)
+ return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(addr);
+ }
+
+-#define pud_page(pud) pfn_to_page(__phys_to_pfn(pud_val(pud) & PHYS_MASK))
+-
+ #endif /* CONFIG_ARM64_PGTABLE_LEVELS > 2 */
+
+ #if CONFIG_ARM64_PGTABLE_LEVELS > 3
+@@ -443,8 +425,6 @@ static inline pud_t *pud_offset(pgd_t *pgd, unsigned long addr)
+ return (pud_t *)pgd_page_vaddr(*pgd) + pud_index(addr);
+ }
+
+-#define pgd_page(pgd) pfn_to_page(__phys_to_pfn(pgd_val(pgd) & PHYS_MASK))
+-
+ #endif /* CONFIG_ARM64_PGTABLE_LEVELS > 3 */
+
+ #define pgd_ERROR(pgd) __pgd_error(__FILE__, __LINE__, pgd_val(pgd))
+diff --git a/arch/arm64/include/asm/tlb.h b/arch/arm64/include/asm/tlb.h
+index c028fe3..62731ef 100644
+--- a/arch/arm64/include/asm/tlb.h
++++ b/arch/arm64/include/asm/tlb.h
+@@ -19,44 +19,84 @@
+ #ifndef __ASM_TLB_H
+ #define __ASM_TLB_H
+
+-#include <linux/pagemap.h>
+-#include <linux/swap.h>
+-
+-#ifdef CONFIG_HAVE_RCU_TABLE_FREE
+-
+-#define tlb_remove_entry(tlb, entry) tlb_remove_table(tlb, entry)
+-static inline void __tlb_remove_table(void *_table)
+-{
+- free_page_and_swap_cache((struct page *)_table);
+-}
+-#else
+-#define tlb_remove_entry(tlb, entry) tlb_remove_page(tlb, entry)
+-#endif /* CONFIG_HAVE_RCU_TABLE_FREE */
++#define __tlb_remove_pmd_tlb_entry __tlb_remove_pmd_tlb_entry
+
+ #include <asm-generic/tlb.h>
+
++/*
++ * There's three ways the TLB shootdown code is used:
++ * 1. Unmapping a range of vmas. See zap_page_range(), unmap_region().
++ * tlb->fullmm = 0, and tlb_start_vma/tlb_end_vma will be called.
++ * 2. Unmapping all vmas. See exit_mmap().
++ * tlb->fullmm = 1, and tlb_start_vma/tlb_end_vma will be called.
++ * Page tables will be freed.
++ * 3. Unmapping argument pages. See shift_arg_pages().
++ * tlb->fullmm = 0, but tlb_start_vma/tlb_end_vma will not be called.
++ */
+ static inline void tlb_flush(struct mmu_gather *tlb)
+ {
+ if (tlb->fullmm) {
+ flush_tlb_mm(tlb->mm);
+- } else {
++ } else if (tlb->end > 0) {
+ struct vm_area_struct vma = { .vm_mm = tlb->mm, };
+ flush_tlb_range(&vma, tlb->start, tlb->end);
++ tlb->start = TASK_SIZE;
++ tlb->end = 0;
++ }
++}
++
++static inline void tlb_add_flush(struct mmu_gather *tlb, unsigned long addr)
++{
++ if (!tlb->fullmm) {
++ tlb->start = min(tlb->start, addr);
++ tlb->end = max(tlb->end, addr + PAGE_SIZE);
+ }
+ }
+
++/*
++ * Memorize the range for the TLB flush.
++ */
++static inline void __tlb_remove_tlb_entry(struct mmu_gather *tlb, pte_t *ptep,
++ unsigned long addr)
++{
++ tlb_add_flush(tlb, addr);
++}
++
++/*
++ * In the case of tlb vma handling, we can optimise these away in the
++ * case where we're doing a full MM flush. When we're doing a munmap,
++ * the vmas are adjusted to only cover the region to be torn down.
++ */
++static inline void tlb_start_vma(struct mmu_gather *tlb,
++ struct vm_area_struct *vma)
++{
++ if (!tlb->fullmm) {
++ tlb->start = TASK_SIZE;
++ tlb->end = 0;
++ }
++}
++
++static inline void tlb_end_vma(struct mmu_gather *tlb,
++ struct vm_area_struct *vma)
++{
++ if (!tlb->fullmm)
++ tlb_flush(tlb);
++}
++
+ static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t pte,
+ unsigned long addr)
+ {
+ pgtable_page_dtor(pte);
+- tlb_remove_entry(tlb, pte);
++ tlb_add_flush(tlb, addr);
++ tlb_remove_page(tlb, pte);
+ }
+
+ #if CONFIG_ARM64_PGTABLE_LEVELS > 2
+ static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmdp,
+ unsigned long addr)
+ {
+- tlb_remove_entry(tlb, virt_to_page(pmdp));
++ tlb_add_flush(tlb, addr);
++ tlb_remove_page(tlb, virt_to_page(pmdp));
+ }
+ #endif
+
+@@ -64,8 +104,15 @@ static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmdp,
+ static inline void __pud_free_tlb(struct mmu_gather *tlb, pud_t *pudp,
+ unsigned long addr)
+ {
+- tlb_remove_entry(tlb, virt_to_page(pudp));
++ tlb_add_flush(tlb, addr);
++ tlb_remove_page(tlb, virt_to_page(pudp));
+ }
+ #endif
+
++static inline void __tlb_remove_pmd_tlb_entry(struct mmu_gather *tlb, pmd_t *pmdp,
++ unsigned long address)
++{
++ tlb_add_flush(tlb, address);
++}
++
+ #endif
+diff --git a/arch/arm64/mm/flush.c b/arch/arm64/mm/flush.c
+index b6f14e8..0d64089 100644
+--- a/arch/arm64/mm/flush.c
++++ b/arch/arm64/mm/flush.c
+@@ -104,19 +104,3 @@ EXPORT_SYMBOL(flush_dcache_page);
+ */
+ EXPORT_SYMBOL(flush_cache_all);
+ EXPORT_SYMBOL(flush_icache_range);
+-
+-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+-#ifdef CONFIG_HAVE_RCU_TABLE_FREE
+-void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address,
+- pmd_t *pmdp)
+-{
+- pmd_t pmd = pmd_mksplitting(*pmdp);
+-
+- VM_BUG_ON(address & ~PMD_MASK);
+- set_pmd_at(vma->vm_mm, address, pmdp, pmd);
+-
+- /* dummy IPI to serialise against fast_gup */
+- kick_all_cpus_sync();
+-}
+-#endif /* CONFIG_HAVE_RCU_TABLE_FREE */
+-#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+diff --git a/include/asm-generic/tlb.h b/include/asm-generic/tlb.h
+index db284bf..5672d7e 100644
+--- a/include/asm-generic/tlb.h
++++ b/include/asm-generic/tlb.h
+@@ -96,9 +96,10 @@ struct mmu_gather {
+ #endif
+ unsigned long start;
+ unsigned long end;
++ unsigned int need_flush : 1, /* Did free PTEs */
+ /* we are in the middle of an operation to clear
+ * a full mm and can make some optimizations */
+- unsigned int fullmm : 1,
++ fullmm : 1,
+ /* we have performed an operation which
+ * requires a complete flush of the tlb */
+ need_flush_all : 1;
+@@ -127,58 +128,16 @@ static inline void tlb_remove_page(struct mmu_gather *tlb, struct page *page)
+ tlb_flush_mmu(tlb);
+ }
+
+-static inline void __tlb_adjust_range(struct mmu_gather *tlb,
+- unsigned long address)
+-{
+- tlb->start = min(tlb->start, address);
+- tlb->end = max(tlb->end, address + PAGE_SIZE);
+-}
+-
+-static inline void __tlb_reset_range(struct mmu_gather *tlb)
+-{
+- if (tlb->fullmm) {
+- tlb->start = tlb->end = ~0;
+- } else {
+- tlb->start = TASK_SIZE;
+- tlb->end = 0;
+- }
+-}
+-
+-/*
+- * In the case of tlb vma handling, we can optimise these away in the
+- * case where we're doing a full MM flush. When we're doing a munmap,
+- * the vmas are adjusted to only cover the region to be torn down.
+- */
+-#ifndef tlb_start_vma
+-#define tlb_start_vma(tlb, vma) do { } while (0)
+-#endif
+-
+-#define __tlb_end_vma(tlb, vma) \
+- do { \
+- if (!tlb->fullmm && tlb->end) { \
+- tlb_flush(tlb); \
+- __tlb_reset_range(tlb); \
+- } \
+- } while (0)
+-
+-#ifndef tlb_end_vma
+-#define tlb_end_vma __tlb_end_vma
+-#endif
+-
+-#ifndef __tlb_remove_tlb_entry
+-#define __tlb_remove_tlb_entry(tlb, ptep, address) do { } while (0)
+-#endif
+-
+ /**
+ * tlb_remove_tlb_entry - remember a pte unmapping for later tlb invalidation.
+ *
+- * Record the fact that pte's were really unmapped by updating the range,
+- * so we can later optimise away the tlb invalidate. This helps when
+- * userspace is unmapping already-unmapped pages, which happens quite a lot.
++ * Record the fact that pte's were really umapped in ->need_flush, so we can
++ * later optimise away the tlb invalidate. This helps when userspace is
++ * unmapping already-unmapped pages, which happens quite a lot.
+ */
+ #define tlb_remove_tlb_entry(tlb, ptep, address) \
+ do { \
+- __tlb_adjust_range(tlb, address); \
++ tlb->need_flush = 1; \
+ __tlb_remove_tlb_entry(tlb, ptep, address); \
+ } while (0)
+
+@@ -192,27 +151,27 @@ static inline void __tlb_reset_range(struct mmu_gather *tlb)
+
+ #define tlb_remove_pmd_tlb_entry(tlb, pmdp, address) \
+ do { \
+- __tlb_adjust_range(tlb, address); \
++ tlb->need_flush = 1; \
+ __tlb_remove_pmd_tlb_entry(tlb, pmdp, address); \
+ } while (0)
+
+ #define pte_free_tlb(tlb, ptep, address) \
+ do { \
+- __tlb_adjust_range(tlb, address); \
++ tlb->need_flush = 1; \
+ __pte_free_tlb(tlb, ptep, address); \
+ } while (0)
+
+ #ifndef __ARCH_HAS_4LEVEL_HACK
+ #define pud_free_tlb(tlb, pudp, address) \
+ do { \
+- __tlb_adjust_range(tlb, address); \
++ tlb->need_flush = 1; \
+ __pud_free_tlb(tlb, pudp, address); \
+ } while (0)
+ #endif
+
+ #define pmd_free_tlb(tlb, pmdp, address) \
+ do { \
+- __tlb_adjust_range(tlb, address); \
++ tlb->need_flush = 1; \
+ __pmd_free_tlb(tlb, pmdp, address); \
+ } while (0)
+
+diff --git a/mm/memory.c b/mm/memory.c
+index 411144f..2772d7a 100644
+--- a/mm/memory.c
++++ b/mm/memory.c
+@@ -220,6 +220,9 @@ void tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm, unsigned long
+ /* Is it from 0 to ~0? */
+ tlb->fullmm = !(start | (end+1));
+ tlb->need_flush_all = 0;
++ tlb->start = start;
++ tlb->end = end;
++ tlb->need_flush = 0;
+ tlb->local.next = NULL;
+ tlb->local.nr = 0;
+ tlb->local.max = ARRAY_SIZE(tlb->__pages);
+@@ -229,28 +232,23 @@ void tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm, unsigned long
+ #ifdef CONFIG_HAVE_RCU_TABLE_FREE
+ tlb->batch = NULL;
+ #endif
+-
+- __tlb_reset_range(tlb);
+ }
+
+ static void tlb_flush_mmu_tlbonly(struct mmu_gather *tlb)
+ {
+- if (!tlb->end)
+- return;
+-
++ tlb->need_flush = 0;
+ tlb_flush(tlb);
+ mmu_notifier_invalidate_range(tlb->mm, tlb->start, tlb->end);
+ #ifdef CONFIG_HAVE_RCU_TABLE_FREE
+ tlb_table_flush(tlb);
+ #endif
+- __tlb_reset_range(tlb);
+ }
+
+ static void tlb_flush_mmu_free(struct mmu_gather *tlb)
+ {
+ struct mmu_gather_batch *batch;
+
+- for (batch = &tlb->local; batch && batch->nr; batch = batch->next) {
++ for (batch = &tlb->local; batch; batch = batch->next) {
+ free_pages_and_swap_cache(batch->pages, batch->nr);
+ batch->nr = 0;
+ }
+@@ -259,6 +257,8 @@ static void tlb_flush_mmu_free(struct mmu_gather *tlb)
+
+ void tlb_flush_mmu(struct mmu_gather *tlb)
+ {
++ if (!tlb->need_flush)
++ return;
+ tlb_flush_mmu_tlbonly(tlb);
+ tlb_flush_mmu_free(tlb);
+ }
+@@ -293,7 +293,7 @@ int __tlb_remove_page(struct mmu_gather *tlb, struct page *page)
+ {
+ struct mmu_gather_batch *batch;
+
+- VM_BUG_ON(!tlb->end);
++ VM_BUG_ON(!tlb->need_flush);
+
+ batch = tlb->active;
+ batch->pages[batch->nr++] = page;
+@@ -360,6 +360,8 @@ void tlb_remove_table(struct mmu_gather *tlb, void *table)
+ {
+ struct mmu_table_batch **batch = &tlb->batch;
+
++ tlb->need_flush = 1;
++
+ /*
+ * When there's less then two users of this mm there cannot be a
+ * concurrent page-table walk.
+@@ -1161,8 +1163,20 @@ again:
+ arch_leave_lazy_mmu_mode();
+
+ /* Do the actual TLB flush before dropping ptl */
+- if (force_flush)
++ if (force_flush) {
++ unsigned long old_end;
++
++ /*
++ * Flush the TLB just for the previous segment,
++ * then update the range to be the remaining
++ * TLB range.
++ */
++ old_end = tlb->end;
++ tlb->end = addr;
+ tlb_flush_mmu_tlbonly(tlb);
++ tlb->start = addr;
++ tlb->end = old_end;
++ }
+ pte_unmap_unlock(start_pte, ptl);
+
+ /*
diff --git a/kernel.spec b/kernel.spec
index 3a1891e..66b28f7 100644
--- a/kernel.spec
+++ b/kernel.spec
@@ -660,6 +660,7 @@ Patch26168: HID-multitouch-add-support-of-clickpads.patch
# git clone ssh://git.fedorahosted.org/git/kernel-arm64.git, git diff master...devel
Patch30000: kernel-arm64.patch
+Patch30001: arm64-revert-tlb-rcu_table_free.patch
# END OF PATCH DEFINITIONS
@@ -1422,8 +1423,10 @@ ApplyPatch HID-multitouch-add-support-of-clickpads.patch
%if 0%{?aarch64patches}
ApplyPatch kernel-arm64.patch
+ApplyPatch arm64-revert-tlb-rcu_table_free.patch
%ifnarch aarch64 # this is stupid, but i want to notice before secondary koji does.
ApplyPatch kernel-arm64.patch -R
+ApplyPatch arm64-revert-tlb-rcu_table_free.patch -R
%endif
%endif
@@ -2277,6 +2280,10 @@ fi
#
#
%changelog
+* Fri Mar 13 2015 Kyle McMartin <kyle at fedoraproject.org>
+- arm64-revert-tlb-rcu_table_free.patch: revert 5e5f6dc1 which
+ causes lockups on arm64 machines.
+
* Fri Mar 13 2015 Josh Boyer <jwboyer at fedoraproject.org> - 4.0.0-0.rc3.git2.1
- Linux v4.0-rc3-148-gc202baf017ae
- Add patch to support clickpads (rhbz 1201532)
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