linux-kernel - [12/16] export __get_user_pages

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:	Fri, 16 Dec 2011 12:49:45 -0800
From:	Greg KH <gregkh@...e.de>
To:	linux-kernel@...r.kernel.org, stable@...r.kernel.org,
	Greg KH <greg@...ah.com>
Cc:	torvalds@...ux-foundation.org, akpm@...ux-foundation.org,
	alan@...rguk.ukuu.org.uk,
	oprofile-list <oprofile-list@...ts.sourceforge.net>,
	Nick Piggin <npiggin@...e.de>,
	Xiao Guangrong <xiaoguangrong@...fujitsu.com>,
	Marcelo Tosatti <mtosatti@...hat.com>,
	Robert Richter <robert.richter@....com>
Subject: [12/16] export __get_user_pages_fast() function

2.6.32-longterm review patch.  If anyone has any objections, please let me know.

------------------


From: Xiao Guangrong <xiaoguangrong@...fujitsu.com>

commit 45888a0c6edc305495b6bd72a30e66bc40b324c6 upstream.

Backport for stable kernel v2.6.32.y to v2.6.36.y.

Needed for next patch:

 oprofile, x86: Fix nmi-unsafe callgraph support

This function is used by KVM to pin process's page in the atomic context.

Define the 'weak' function to avoid other architecture not support it

Acked-by: Nick Piggin <npiggin@...e.de>
Signed-off-by: Xiao Guangrong <xiaoguangrong@...fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@...hat.com>
Signed-off-by: Robert Richter <robert.richter@....com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...e.de>
---
 mm/util.c |   13 +++++++++++++
 1 file changed, 13 insertions(+)

--- a/mm/util.c
+++ b/mm/util.c
@@ -233,6 +233,19 @@ void arch_pick_mmap_layout(struct mm_str
 }
 #endif
 
+/*
+ * Like get_user_pages_fast() except its IRQ-safe in that it won't fall
+ * back to the regular GUP.
+ * If the architecture not support this fucntion, simply return with no
+ * page pinned
+ */
+int __attribute__((weak)) __get_user_pages_fast(unsigned long start,
+				 int nr_pages, int write, struct page **pages)
+{
+	return 0;
+}
+EXPORT_SYMBOL_GPL(__get_user_pages_fast);
+
 /**
  * get_user_pages_fast() - pin user pages in memory
  * @start:	starting user address


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/