The quilt patch titled
Subject: dax: fix incorrect list of data cache aliasing architectures
has been removed from the -mm tree. Its filename was
dax-fix-incorrect-list-of-data-cache-aliasing-architectures.patch
This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
Subject: dax: fix incorrect list of data cache aliasing architectures
Date: Thu, 15 Feb 2024 09:46:33 -0500
commit d92576f1167c ("dax: does not work correctly with virtual aliasing caches")
prevents DAX from building on architectures with virtually aliased
dcache with:
depends on !(ARM || MIPS || SPARC)
This check is too broad (e.g. recent ARMv7 don't have virtually aliased
dcaches), and also misses many other architectures with virtually
aliased data cache.
This is a regression introduced in the v4.0 Linux kernel where the
dax mount option is removed for 32-bit ARMv7 boards which have no data
cache aliasing, and therefore should work fine with FS_DAX.
This was turned into the following check in alloc_dax() by a preparatory
change:
if (ops && (IS_ENABLED(CONFIG_ARM) ||
IS_ENABLED(CONFIG_MIPS) ||
IS_ENABLED(CONFIG_SPARC)))
return NULL;
Use cpu_dcache_is_aliasing() instead to figure out whether the environment
has aliasing data caches.
Link: https://lkml.kernel.org/r/20240215144633.96437-10-mathieu.desnoyers@xxxxxxxxxxxx
Fixes: d92576f1167c ("dax: does not work correctly with virtual aliasing caches")
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
Reviewed-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: Vishal Verma <vishal.l.verma@xxxxxxxxx>
Cc: Dave Jiang <dave.jiang@xxxxxxxxx>
Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: Russell King <linux@xxxxxxxxxxxxxxx>
Cc: Alasdair Kergon <agk@xxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Dave Chinner <david@xxxxxxxxxxxxx>
Cc: Heiko Carstens <hca@xxxxxxxxxxxxx>
Cc: kernel test robot <lkp@xxxxxxxxx>
Cc: Michael Sclafani <dm-devel@xxxxxxxxxxxxxxx>
Cc: Mike Snitzer <snitzer@xxxxxxxxxx>
Cc: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/dax/super.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
--- a/drivers/dax/super.c~dax-fix-incorrect-list-of-data-cache-aliasing-architectures
+++ a/drivers/dax/super.c
@@ -13,6 +13,7 @@
#include <linux/uio.h>
#include <linux/dax.h>
#include <linux/fs.h>
+#include <linux/cacheinfo.h>
#include "dax-private.h"
/**
@@ -456,9 +457,7 @@ struct dax_device *alloc_dax(void *priva
* except for device-dax (NULL operations pointer), which does
* not use aliased mappings from the kernel.
*/
- if (ops && (IS_ENABLED(CONFIG_ARM) ||
- IS_ENABLED(CONFIG_MIPS) ||
- IS_ENABLED(CONFIG_SPARC)))
+ if (ops && cpu_dcache_is_aliasing())
return ERR_PTR(-EOPNOTSUPP);
if (WARN_ON_ONCE(ops && !ops->zero_page_range))
_
Patches currently in -mm which might be from mathieu.desnoyers@xxxxxxxxxxxx are
