From: Wupeng Ma <mawupeng1@huawei.com> hulk inclusion category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/ID6J4B -------------------------------- Introduce copy_mc_highpage{s} to properly handle uncorrectable memory errors (UCE) during kernel page copies. Rather than panicking on hardware memory errors, the implementation now safely propagates the error condition. Signed-off-by: Wupeng Ma <mawupeng1@huawei.com> Signed-off-by: Qi Xi <xiqi2@huawei.com> --- include/linux/highmem.h | 55 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) diff --git a/include/linux/highmem.h b/include/linux/highmem.h index 1fed918bb1e5..0baeb9112e63 100644 --- a/include/linux/highmem.h +++ b/include/linux/highmem.h @@ -267,6 +267,61 @@ static inline void copy_highpage(struct page *to, struct page *from) kunmap_atomic(vfrom); } +#ifdef CONFIG_UCE_KERNEL_RECOVERY +/* Return -EFAULT if there was a #MC during copy, otherwise 0 for success. */ +static inline int copy_mc_highpage(struct page *to, struct page *from) +{ + char *vfrom, *vto; + int ret; + + vfrom = kmap_atomic(from); + vto = kmap_atomic(to); + ret = copy_page_cow(vto, vfrom); + kunmap_atomic(vto); + kunmap_atomic(vfrom); + + return ret; +} + +/* Return -EFAULT if there was a #MC during copy, otherwise 0 for success. */ +static inline int copy_mc_highpages(struct page *to, struct page *from, + int nr_pages) +{ + int ret = 0; + int i; + + for (i = 0; i < nr_pages; i++) { + cond_resched(); + ret = copy_mc_highpage(to + i, from + i); + if (ret) + return -EFAULT; + } + + return ret; +} +#else +static inline int copy_mc_highpage(struct page *to, struct page *from) +{ + copy_highpage(to, from); + + return 0; +} + +/* Return -EFAULT if there was a #MC during copy, otherwise 0 for success. */ +static inline int copy_mc_highpages(struct page *to, struct page *from, + int nr_pages) +{ + int i; + + for (i = 0; i < nr_pages; i++) { + cond_resched(); + (void)copy_mc_highpage(to + i, from + i); + } + + return 0; +} +#endif + #endif #endif /* _LINUX_HIGHMEM_H */ -- 2.33.0