From 481535c5b41d191b22775a6873de5ec0e1cdced1 Mon Sep 17 00:00:00 2001 From: Max Filippov Date: Mon, 16 Nov 2020 01:25:56 -0800 Subject: xtensa: fix TLBTEMP area placement fast_second_level_miss handler for the TLBTEMP area has an assumption that page table directory entry for the TLBTEMP address range is 0. For it to be true the TLBTEMP area must be aligned to 4MB boundary and not share its 4MB region with anything that may use a page table. This is not true currently: TLBTEMP shares space with vmalloc space which results in the following kinds of runtime errors when fast_second_level_miss loads page table directory entry for the vmalloc space instead of fixing up the TLBTEMP area: Unable to handle kernel paging request at virtual address c7ff0e00 pc = d0009275, ra = 90009478 Oops: sig: 9 [#1] PREEMPT CPU: 1 PID: 61 Comm: kworker/u9:2 Not tainted 5.10.0-rc3-next-20201110-00007-g1fe4962fa983-dirty #58 Workqueue: xprtiod xs_stream_data_receive_workfn a00: 90009478 d11e1dc0 c7ff0e00 00000020 c7ff0000 00000001 7f8b8107 00000000 a08: 900c5992 d11e1d90 d0cc88b8 5506e97c 00000000 5506e97c d06c8074 d11e1d90 pc: d0009275, ps: 00060310, depc: 00000014, excvaddr: c7ff0e00 lbeg: d0009275, lend: d0009287 lcount: 00000003, sar: 00000010 Call Trace: xs_stream_data_receive_workfn+0x43c/0x770 process_one_work+0x1a1/0x324 worker_thread+0x1cc/0x3c0 kthread+0x10d/0x124 ret_from_kernel_thread+0xc/0x18 Cc: stable@vger.kernel.org Signed-off-by: Max Filippov --- arch/xtensa/include/asm/pgtable.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch') diff --git a/arch/xtensa/include/asm/pgtable.h b/arch/xtensa/include/asm/pgtable.h index fa054a1772e1..4dc04e6c01d7 100644 --- a/arch/xtensa/include/asm/pgtable.h +++ b/arch/xtensa/include/asm/pgtable.h @@ -69,7 +69,7 @@ */ #define VMALLOC_START (XCHAL_KSEG_CACHED_VADDR - 0x10000000) #define VMALLOC_END (VMALLOC_START + 0x07FEFFFF) -#define TLBTEMP_BASE_1 (VMALLOC_END + 1) +#define TLBTEMP_BASE_1 (VMALLOC_START + 0x08000000) #define TLBTEMP_BASE_2 (TLBTEMP_BASE_1 + DCACHE_WAY_SIZE) #if 2 * DCACHE_WAY_SIZE > ICACHE_WAY_SIZE #define TLBTEMP_SIZE (2 * DCACHE_WAY_SIZE) -- cgit v1.2.3 From 3a860d165eb5f4d7cf0bf81ef6a5b5c5e1754422 Mon Sep 17 00:00:00 2001 From: Max Filippov Date: Mon, 16 Nov 2020 01:38:59 -0800 Subject: xtensa: disable preemption around cache alias management calls Although cache alias management calls set up and tear down TLB entries and fast_second_level_miss is able to restore TLB entry should it be evicted they absolutely cannot preempt each other because they use the same TLBTEMP area for different purposes. Disable preemption around all cache alias management calls to enforce that. Cc: stable@vger.kernel.org Signed-off-by: Max Filippov --- arch/xtensa/mm/cache.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'arch') diff --git a/arch/xtensa/mm/cache.c b/arch/xtensa/mm/cache.c index 5835406b3cec..085b8c77b9d9 100644 --- a/arch/xtensa/mm/cache.c +++ b/arch/xtensa/mm/cache.c @@ -70,8 +70,10 @@ static inline void kmap_invalidate_coherent(struct page *page, kvaddr = TLBTEMP_BASE_1 + (page_to_phys(page) & DCACHE_ALIAS_MASK); + preempt_disable(); __invalidate_dcache_page_alias(kvaddr, page_to_phys(page)); + preempt_enable(); } } } @@ -156,6 +158,7 @@ void flush_dcache_page(struct page *page) if (!alias && !mapping) return; + preempt_disable(); virt = TLBTEMP_BASE_1 + (phys & DCACHE_ALIAS_MASK); __flush_invalidate_dcache_page_alias(virt, phys); @@ -166,6 +169,7 @@ void flush_dcache_page(struct page *page) if (mapping) __invalidate_icache_page_alias(virt, phys); + preempt_enable(); } /* There shouldn't be an entry in the cache for this page anymore. */ @@ -199,8 +203,10 @@ void local_flush_cache_page(struct vm_area_struct *vma, unsigned long address, unsigned long phys = page_to_phys(pfn_to_page(pfn)); unsigned long virt = TLBTEMP_BASE_1 + (address & DCACHE_ALIAS_MASK); + preempt_disable(); __flush_invalidate_dcache_page_alias(virt, phys); __invalidate_icache_page_alias(virt, phys); + preempt_enable(); } EXPORT_SYMBOL(local_flush_cache_page); @@ -227,11 +233,13 @@ update_mmu_cache(struct vm_area_struct * vma, unsigned long addr, pte_t *ptep) unsigned long phys = page_to_phys(page); unsigned long tmp; + preempt_disable(); tmp = TLBTEMP_BASE_1 + (phys & DCACHE_ALIAS_MASK); __flush_invalidate_dcache_page_alias(tmp, phys); tmp = TLBTEMP_BASE_1 + (addr & DCACHE_ALIAS_MASK); __flush_invalidate_dcache_page_alias(tmp, phys); __invalidate_icache_page_alias(tmp, phys); + preempt_enable(); clear_bit(PG_arch_1, &page->flags); } @@ -265,7 +273,9 @@ void copy_to_user_page(struct vm_area_struct *vma, struct page *page, if (alias) { unsigned long t = TLBTEMP_BASE_1 + (vaddr & DCACHE_ALIAS_MASK); + preempt_disable(); __flush_invalidate_dcache_page_alias(t, phys); + preempt_enable(); } /* Copy data */ @@ -280,9 +290,11 @@ void copy_to_user_page(struct vm_area_struct *vma, struct page *page, if (alias) { unsigned long t = TLBTEMP_BASE_1 + (vaddr & DCACHE_ALIAS_MASK); + preempt_disable(); __flush_invalidate_dcache_range((unsigned long) dst, len); if ((vma->vm_flags & VM_EXEC) != 0) __invalidate_icache_page_alias(t, phys); + preempt_enable(); } else if ((vma->vm_flags & VM_EXEC) != 0) { __flush_dcache_range((unsigned long)dst,len); @@ -304,7 +316,9 @@ extern void copy_from_user_page(struct vm_area_struct *vma, struct page *page, if (alias) { unsigned long t = TLBTEMP_BASE_1 + (vaddr & DCACHE_ALIAS_MASK); + preempt_disable(); __flush_invalidate_dcache_page_alias(t, phys); + preempt_enable(); } memcpy(dst, src, len); -- cgit v1.2.3 From dc293f2106903ab9c24e9cea18c276e32c394c33 Mon Sep 17 00:00:00 2001 From: Laurent Pinchart Date: Tue, 1 Sep 2020 00:09:37 +0300 Subject: xtensa: uaccess: Add missing __user to strncpy_from_user() prototype When adding __user annotations in commit 2adf5352a34a, the strncpy_from_user() function declaration for the CONFIG_GENERIC_STRNCPY_FROM_USER case was missed. Fix it. Reported-by: kernel test robot Signed-off-by: Laurent Pinchart Message-Id: <20200831210937.17938-1-laurent.pinchart@ideasonboard.com> Signed-off-by: Max Filippov --- arch/xtensa/include/asm/uaccess.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch') diff --git a/arch/xtensa/include/asm/uaccess.h b/arch/xtensa/include/asm/uaccess.h index b9758119feca..5c9fb8005aa8 100644 --- a/arch/xtensa/include/asm/uaccess.h +++ b/arch/xtensa/include/asm/uaccess.h @@ -302,7 +302,7 @@ strncpy_from_user(char *dst, const char __user *src, long count) return -EFAULT; } #else -long strncpy_from_user(char *dst, const char *src, long count); +long strncpy_from_user(char *dst, const char __user *src, long count); #endif /* -- cgit v1.2.3