[PATCH AUTOSEL 4.19 07/55] hugetlb: clear huge pte during flush function on mips platform

[PATCH AUTOSEL 4.19 07/55] hugetlb: clear huge pte during flush function on mips platform

[Sasha Levin]

From: Bibo Mao <maobibo@loongson.cn>

[ Upstream commit 33ae8f801ad8bec48e886d368739feb2816478f2 ]

If multiple threads are accessing the same huge page at the same
time, hugetlb_cow will be called if one thread write the COW huge
page. And function huge_ptep_clear_flush is called to notify other
threads to clear the huge pte tlb entry. The other threads clear
the huge pte tlb entry and reload it from page table, the reload
huge pte entry may be old.

This patch fixes this issue on mips platform, and it clears huge
pte entry before notifying other threads to flush current huge
page entry, it is similar with other architectures.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/mips/include/asm/hugetlb.h | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/arch/mips/include/asm/hugetlb.h b/arch/mips/include/asm/hugetlb.h
index 982bc0685330..4747a4694669 100644
--- a/arch/mips/include/asm/hugetlb.h
+++ b/arch/mips/include/asm/hugetlb.h
@@ -67,7 +67,13 @@ static inline pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
 static inline void huge_ptep_clear_flush(struct vm_area_struct *vma,
 					 unsigned long addr, pte_t *ptep)
 {
-	flush_tlb_page(vma, addr & huge_page_mask(hstate_vma(vma)));
+	/*
+	 * clear the huge pte entry firstly, so that the other smp threads will
+	 * not get old pte entry after finishing flush_tlb_page and before
+	 * setting new huge pte entry
+	 */
+	huge_ptep_get_and_clear(vma->vm_mm, addr, ptep);
+	flush_tlb_page(vma, addr);
 }
 
 static inline int huge_pte_none(pte_t pte)
-- 
2.30.2

[PATCH AUTOSEL 4.19 37/55] MIPS: add PMD table accounting into MIPS'pmd_alloc_one

[Sasha Levin]

From: Huang Pei <huangpei@loongson.cn>

[ Upstream commit ed914d48b6a1040d1039d371b56273d422c0081e ]

This fixes Page Table accounting bug.

MIPS is the ONLY arch just defining __HAVE_ARCH_PMD_ALLOC_ONE alone.
Since commit b2b29d6d011944 (mm: account PMD tables like PTE tables),
"pmd_free" in asm-generic with PMD table accounting and "pmd_alloc_one"
in MIPS without PMD table accounting causes PageTable accounting number
negative, which read by global_zone_page_state(), always returns 0.

Signed-off-by: Huang Pei <huangpei@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/mips/include/asm/pgalloc.h | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/arch/mips/include/asm/pgalloc.h b/arch/mips/include/asm/pgalloc.h
index 39b9f311c4ef..f800872f867b 100644
--- a/arch/mips/include/asm/pgalloc.h
+++ b/arch/mips/include/asm/pgalloc.h
@@ -93,11 +93,15 @@ do {							\
 
 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address)
 {
-	pmd_t *pmd;
+	pmd_t *pmd = NULL;
+	struct page *pg;
 
-	pmd = (pmd_t *) __get_free_pages(GFP_KERNEL, PMD_ORDER);
-	if (pmd)
+	pg = alloc_pages(GFP_KERNEL | __GFP_ACCOUNT, PMD_ORDER);
+	if (pg) {
+		pgtable_pmd_page_ctor(pg);
+		pmd = (pmd_t *)page_address(pg);
 		pmd_init((unsigned long)pmd, (unsigned long)invalid_pte_table);
+	}
 	return pmd;
 }
 
-- 
2.30.2

[PATCH AUTOSEL 4.19 55/55] MIPS: set mips32r5 for virt extensions

[Sasha Levin]

From: Nick Desaulniers <ndesaulniers@google.com>

[ Upstream commit c994a3ec7ecc8bd2a837b2061e8a76eb8efc082b ]

Clang's integrated assembler only accepts these instructions when the
cpu is set to mips32r5. With this change, we can assemble
malta_defconfig with Clang via `make LLVM_IAS=1`.

Link: https://github.com/ClangBuiltLinux/linux/issues/763
Reported-by: Dmitry Golovin <dima@golovin.in>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/mips/include/asm/mipsregs.h | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/mips/include/asm/mipsregs.h b/arch/mips/include/asm/mipsregs.h
index f9a7c137be9f..c8333782a670 100644
--- a/arch/mips/include/asm/mipsregs.h
+++ b/arch/mips/include/asm/mipsregs.h
@@ -1986,7 +1986,7 @@ _ASM_MACRO_0(tlbginvf, _ASM_INSN_IF_MIPS(0x4200000c)
 ({ int __res;								\
 	__asm__ __volatile__(						\
 		".set\tpush\n\t"					\
-		".set\tmips32r2\n\t"					\
+		".set\tmips32r5\n\t"					\
 		_ASM_SET_VIRT						\
 		"mfgc0\t%0, " #source ", %1\n\t"			\
 		".set\tpop"						\
@@ -1999,7 +1999,7 @@ _ASM_MACRO_0(tlbginvf, _ASM_INSN_IF_MIPS(0x4200000c)
 ({ unsigned long long __res;						\
 	__asm__ __volatile__(						\
 		".set\tpush\n\t"					\
-		".set\tmips64r2\n\t"					\
+		".set\tmips64r5\n\t"					\
 		_ASM_SET_VIRT						\
 		"dmfgc0\t%0, " #source ", %1\n\t"			\
 		".set\tpop"						\
@@ -2012,7 +2012,7 @@ _ASM_MACRO_0(tlbginvf, _ASM_INSN_IF_MIPS(0x4200000c)
 do {									\
 	__asm__ __volatile__(						\
 		".set\tpush\n\t"					\
-		".set\tmips32r2\n\t"					\
+		".set\tmips32r5\n\t"					\
 		_ASM_SET_VIRT						\
 		"mtgc0\t%z0, " #register ", %1\n\t"			\
 		".set\tpop"						\
@@ -2024,7 +2024,7 @@ do {									\
 do {									\
 	__asm__ __volatile__(						\
 		".set\tpush\n\t"					\
-		".set\tmips64r2\n\t"					\
+		".set\tmips64r5\n\t"					\
 		_ASM_SET_VIRT						\
 		"dmtgc0\t%z0, " #register ", %1\n\t"			\
 		".set\tpop"						\
-- 
2.30.2