[merged] proc-stat-convert-to-single_open_size.patch removed from -mm tree

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



The patch titled
     Subject: /proc/stat: convert to single_open_size()
has been removed from the -mm tree.  Its filename was
     proc-stat-convert-to-single_open_size.patch

This patch was dropped because it was merged into mainline or a subsystem tree

------------------------------------------------------
From: Heiko Carstens <heiko.carstens@xxxxxxxxxx>
Subject: /proc/stat: convert to single_open_size()

These two patches are supposed to "fix" failed order-4 memory allocations
which have been observed when reading /proc/stat.  The problem has been
observed on s390 as well as on x86.

To address the problem change the seq_file memory allocations to fallback
to use vmalloc, so that allocations also work if memory is fragmented.

This approach seems to be simpler and less intrusive than changing
/proc/stat to use an interator.  Also it "fixes" other users as well,
which use seq_file's single_open() interface.


This patch (of 2):

Use seq_file's single_open_size() to preallocate a buffer that is large
enough to hold the whole output, instead of open coding it.  Also
calculate the requested size using the number of online cpus instead of
possible cpus, since the size of the output only depends on the number of
online cpus.

Signed-off-by: Heiko Carstens <heiko.carstens@xxxxxxxxxx>
Acked-by: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Ian Kent <raven@xxxxxxxxxx>
Cc: Hendrik Brueckner <brueckner@xxxxxxxxxxxxxxxxxx>
Cc: Thorsten Diehl <thorsten.diehl@xxxxxxxxxx>
Cc: Andrea Righi <andrea@xxxxxxxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx>
Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Stefan Bader <stefan.bader@xxxxxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---

 fs/proc/stat.c |   22 ++--------------------
 1 file changed, 2 insertions(+), 20 deletions(-)

diff -puN fs/proc/stat.c~proc-stat-convert-to-single_open_size fs/proc/stat.c
--- a/fs/proc/stat.c~proc-stat-convert-to-single_open_size
+++ a/fs/proc/stat.c
@@ -184,29 +184,11 @@ static int show_stat(struct seq_file *p,
 
 static int stat_open(struct inode *inode, struct file *file)
 {
-	size_t size = 1024 + 128 * num_possible_cpus();
-	char *buf;
-	struct seq_file *m;
-	int res;
+	size_t size = 1024 + 128 * num_online_cpus();
 
 	/* minimum size to display an interrupt count : 2 bytes */
 	size += 2 * nr_irqs;
-
-	/* don't ask for more than the kmalloc() max size */
-	if (size > KMALLOC_MAX_SIZE)
-		size = KMALLOC_MAX_SIZE;
-	buf = kmalloc(size, GFP_KERNEL);
-	if (!buf)
-		return -ENOMEM;
-
-	res = single_open(file, show_stat, NULL);
-	if (!res) {
-		m = file->private_data;
-		m->buf = buf;
-		m->size = ksize(buf);
-	} else
-		kfree(buf);
-	return res;
+	return single_open_size(file, show_stat, NULL, size);
 }
 
 static const struct file_operations proc_stat_operations = {
_

Patches currently in -mm which might be from heiko.carstens@xxxxxxxxxx are

lib-scatterlist-make-arch_has_sg_chain-an-actual-kconfig.patch
lib-scatterlist-clean-up-useless-architecture-versions-of-scatterlisth.patch
linux-next.patch

--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]