linux-kernel - [PATCH 4/4] mm/vmalloc: remove vfree

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu, 30 Mar 2017 13:27:19 +0300
From:   Andrey Ryabinin <aryabinin@...tuozzo.com>
To:     <akpm@...ux-foundation.org>
CC:     <penguin-kernel@...ove.SAKURA.ne.jp>,
        <linux-kernel@...r.kernel.org>,
        Andrey Ryabinin <aryabinin@...tuozzo.com>, <mhocko@...nel.org>,
        <linux-mm@...ck.org>, <hpa@...or.com>, <chris@...is-wilson.co.uk>,
        <hch@....de>, <mingo@...e.hu>, <jszhang@...vell.com>,
        <joelaf@...gle.com>, <joaodias@...gle.com>, <willy@...radead.org>,
        <tglx@...utronix.de>
Subject: [PATCH 4/4] mm/vmalloc: remove vfree_atomic()

vfree() can be used in any atomic context and there is no
vfree_atomic() callers left, so let's remove it.

This reverts commit bf22e37a6413 ("mm: add vfree_atomic()")

Signed-off-by: Andrey Ryabinin <aryabinin@...tuozzo.com>
---
 include/linux/vmalloc.h |  1 -
 mm/vmalloc.c            | 40 +++++-----------------------------------
 2 files changed, 5 insertions(+), 36 deletions(-)

diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
index 46991ad..b4f044f 100644
--- a/include/linux/vmalloc.h
+++ b/include/linux/vmalloc.h
@@ -83,7 +83,6 @@ extern void *__vmalloc_node_range(unsigned long size, unsigned long align,
 extern void *__vmalloc_node_flags(unsigned long size, int node, gfp_t flags);
 
 extern void vfree(const void *addr);
-extern void vfree_atomic(const void *addr);
 
 extern void *vmap(struct page **pages, unsigned int count,
 			unsigned long flags, pgprot_t prot);
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index ea1b4ab..b77337a 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -1534,38 +1534,6 @@ static void __vunmap(const void *addr, int deallocate_pages)
 	return;
 }
 
-static inline void __vfree_deferred(const void *addr)
-{
-	/*
-	 * Use raw_cpu_ptr() because this can be called from preemptible
-	 * context. Preemption is absolutely fine here, because the llist_add()
-	 * implementation is lockless, so it works even if we are adding to
-	 * nother cpu's list.  schedule_work() should be fine with this too.
-	 */
-	struct vfree_deferred *p = raw_cpu_ptr(&vfree_deferred);
-
-	if (llist_add((struct llist_node *)addr, &p->list))
-		schedule_work(&p->wq);
-}
-
-/**
- *	vfree_atomic  -  release memory allocated by vmalloc()
- *	@addr:		memory base address
- *
- *	This one is just like vfree() but can be called in any atomic context
- *	except NMIs.
- */
-void vfree_atomic(const void *addr)
-{
-	BUG_ON(in_nmi());
-
-	kmemleak_free(addr);
-
-	if (!addr)
-		return;
-	__vfree_deferred(addr);
-}
-
 /**
  *	vfree  -  release memory allocated by vmalloc()
  *	@addr:		memory base address
@@ -1588,9 +1556,11 @@ void vfree(const void *addr)
 
 	if (!addr)
 		return;
-	if (unlikely(in_interrupt()))
-		__vfree_deferred(addr);
-	else
+	if (unlikely(in_interrupt())) {
+		struct vfree_deferred *p = this_cpu_ptr(&vfree_deferred);
+		if (llist_add((struct llist_node *)addr, &p->list))
+			schedule_work(&p->wq);
+	} else
 		__vunmap(addr, 1);
 }
 EXPORT_SYMBOL(vfree);
-- 
2.10.2