diff options
Diffstat (limited to 'arch/powerpc/perf/callchain_64.c')
| -rw-r--r-- | arch/powerpc/perf/callchain_64.c | 27 |
1 files changed, 0 insertions, 27 deletions
diff --git a/arch/powerpc/perf/callchain_64.c b/arch/powerpc/perf/callchain_64.c index 8d0df4226328..488e8a21a11e 100644 --- a/arch/powerpc/perf/callchain_64.c +++ b/arch/powerpc/perf/callchain_64.c @@ -18,33 +18,6 @@ #include "callchain.h" -/* - * On 64-bit we don't want to invoke hash_page on user addresses from - * interrupt context, so if the access faults, we read the page tables - * to find which page (if any) is mapped and access it directly. Radix - * has no need for this so it doesn't use read_user_stack_slow. - */ -int read_user_stack_slow(const void __user *ptr, void *buf, int nb) -{ - - unsigned long addr = (unsigned long) ptr; - unsigned long offset; - struct page *page; - void *kaddr; - - if (get_user_page_fast_only(addr, FOLL_WRITE, &page)) { - kaddr = page_address(page); - - /* align address to page boundary */ - offset = addr & ~PAGE_MASK; - - memcpy(buf, kaddr + offset, nb); - put_page(page); - return 0; - } - return -EFAULT; -} - static int read_user_stack_64(const unsigned long __user *ptr, unsigned long *ret) { return __read_user_stack(ptr, ret, sizeof(*ret)); |