Merge branch 'gate-page-refcount' (patches from Dave Hansen) (8381979d) · Commits · 戴 / test

mm/gup.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -843,7 +843,7 @@ static int get_gate_page(struct mm_struct *mm, unsigned long address,
		goto unmap;
		page = pte_page(pte);
		}
		if (unlikely(!try_get_page(*page))) {
		if (unlikely(!try_grab_page(*page, gup_flags))) {
		ret = -ENOMEM;
		goto unmap;
		}

+20 −2

Original line number	Diff line number	Diff line
		@@ -462,6 +462,17 @@ static int test_vsys_x(void)
		return 0;
		}

		/*
		* Debuggers expect ptrace() to be able to peek at the vsyscall page.
		* Use process_vm_readv() as a proxy for ptrace() to test this. We
		* want it to work in the vsyscall=emulate case and to fail in the
		* vsyscall=xonly case.
		*
		* It's worth noting that this ABI is a bit nutty. write(2) can't
		* read from the vsyscall page on any kernel version or mode. The
		* fact that ptrace() ever worked was a nice courtesy of old kernels,
		* but the code to support it is fairly gross.
		*/
		static int test_process_vm_readv(void)
		{
		#ifdef __x86_64__
		@@ -477,8 +488,12 @@ static int test_process_vm_readv(void)
		remote.iov_len = 4096;
		ret = process_vm_readv(getpid(), &local, 1, &remote, 1, 0);
		if (ret != 4096) {
		printf("[OK]\tprocess_vm_readv() failed (ret = %d, errno = %d)\n", ret, errno);
		return 0;
		/*
		* We expect process_vm_readv() to work if and only if the
		* vsyscall page is readable.
		*/
		printf("[%s]\tprocess_vm_readv() failed (ret = %d, errno = %d)\n", vsyscall_map_r ? "FAIL" : "OK", ret, errno);
		return vsyscall_map_r ? 1 : 0;
		}

		if (vsyscall_map_r) {
		@@ -488,6 +503,9 @@ static int test_process_vm_readv(void)
		printf("[FAIL]\tIt worked but returned incorrect data\n");
		return 1;
		}
		} else {
		printf("[FAIL]\tprocess_rm_readv() succeeded, but it should have failed in this configuration\n");
		return 1;
		}
		#endif