Re: [RFCv2 6/6] mm: extend process_madvise syscall to support vector arrary

Hi Yann,

On Fri, May 31, 2019 at 12:06:52PM +0200, Yann Droneaud wrote:

Hi,

Le vendredi 31 mai 2019 à 15:43 +0900, Minchan Kim a écrit :

quoted

diff --git a/include/uapi/asm-generic/mman-common.h

b/include/uapi/asm-generic/mman-common.h
index 92e347a89ddc..220c2b5eb961 100644

--- a/include/uapi/asm-generic/mman-common.h
+++ b/include/uapi/asm-generic/mman-common.h

@@ -75,4 +75,15 @@
 #define PKEY_ACCESS_MASK	(PKEY_DISABLE_ACCESS |\
 				 PKEY_DISABLE_WRITE)
 
+struct pr_madvise_param {
+	int size;		/* the size of this structure */
+	int cookie;		/* reserved to support atomicity */
+	int nr_elem;		/* count of below arrary fields */

Those should be unsigned.

There's an implicit hole here on ABI with 64bits aligned pointers

quoted

+	int __user *hints;	/* hints for each range */
+	/* to store result of each operation */
+	const struct iovec __user *results;
+	/* input address ranges */
+	const struct iovec __user *ranges;

Using pointer type in uAPI structure require a 'compat' version of the
syscall need to be provided.

If using iovec too.

I will fix them when I submit next revision.
Thanks for the review.