linux_dsm_epyc7002/arch/csky/abiv2/cacheflush.c
Guo Ren 981bbf274b csky: Fixup wrong update_mmu_cache implementation
In our stress test, we found some crash problem caused by:

if (!(vma->vm_flags & VM_EXEC))
	return;

in update_mmu_cache().

Seems current update_mmu_cache implementation is wrong and we retread
to the conservative implementation.

Also the usage of kmap_atomic in update_mmu_cache is risky, page-virtual
may be scheduled out and changed, so we must use preempt_disable &
pagefault_disable which is called by kmap_atomic().

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>
2019-04-22 13:44:57 +08:00

52 lines
1.1 KiB
C

// SPDX-License-Identifier: GPL-2.0
// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
#include <linux/cache.h>
#include <linux/highmem.h>
#include <linux/mm.h>
#include <asm/cache.h>
void flush_icache_page(struct vm_area_struct *vma, struct page *page)
{
unsigned long start;
start = (unsigned long) kmap_atomic(page);
cache_wbinv_range(start, start + PAGE_SIZE);
kunmap_atomic((void *)start);
}
void flush_icache_user_range(struct vm_area_struct *vma, struct page *page,
unsigned long vaddr, int len)
{
unsigned long kaddr;
kaddr = (unsigned long) kmap_atomic(page) + (vaddr & ~PAGE_MASK);
cache_wbinv_range(kaddr, kaddr + len);
kunmap_atomic((void *)kaddr);
}
void update_mmu_cache(struct vm_area_struct *vma, unsigned long address,
pte_t *pte)
{
unsigned long addr, pfn;
struct page *page;
pfn = pte_pfn(*pte);
if (unlikely(!pfn_valid(pfn)))
return;
page = pfn_to_page(pfn);
if (page == ZERO_PAGE(0))
return;
addr = (unsigned long) kmap_atomic(page);
cache_wbinv_range(addr, addr + PAGE_SIZE);
kunmap_atomic((void *) addr);
}