From: Christian Borntraeger <borntraeger(a)de.ibm.com>
Subject: mm: do not drop unused pages when userfaultd is running
KVM guests on s390 can notify the host of unused pages. This can result
in pte_unused callbacks to be true for KVM guest memory.
If a page is unused (checked with pte_unused) we might drop this page
instead of paging it. This can have side-effects on userfaultd, when the
page in question was already migrated:
The next access of that page will trigger a fault and a user fault instead
of faulting in a new and empty zero page. As QEMU does not expect a
userfault on an already migrated page this migration will fail.
The most straightforward solution is to ignore the pte_unused hint if a
userfault context is active for this VMA.
Link: http://lkml.kernel.org/r/20180703171854.63981-1-borntraeger@de.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger(a)de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky(a)de.ibm.com>
Cc: Andrea Arcangeli <aarcange(a)redhat.com>
Cc: Mike Rapoport <rppt(a)linux.vnet.ibm.com>
Cc: Janosch Frank <frankja(a)linux.ibm.com>
Cc: David Hildenbrand <david(a)redhat.com>
Cc: Cornelia Huck <cohuck(a)redhat.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
mm/rmap.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff -puN mm/rmap.c~mm-do-not-drop-unused-pages-when-userfaultd-is-running mm/rmap.c
--- a/mm/rmap.c~mm-do-not-drop-unused-pages-when-userfaultd-is-running
+++ a/mm/rmap.c
@@ -64,6 +64,7 @@
#include <linux/backing-dev.h>
#include <linux/page_idle.h>
#include <linux/memremap.h>
+#include <linux/userfaultfd_k.h>
#include <asm/tlbflush.h>
@@ -1481,11 +1482,16 @@ static bool try_to_unmap_one(struct page
set_pte_at(mm, address, pvmw.pte, pteval);
}
- } else if (pte_unused(pteval)) {
+ } else if (pte_unused(pteval) && !userfaultfd_armed(vma)) {
/*
* The guest indicated that the page content is of no
* interest anymore. Simply discard the pte, vmscan
* will take care of the rest.
+ * A future reference will then fault in a new zero
+ * page. When userfaultfd is active, we must not drop
+ * this page though, as its main user (postcopy
+ * migration) will not expect userfaults on already
+ * copied pages.
*/
dec_mm_counter(mm, mm_counter(page));
/* We have to invalidate as we cleared the pte */
_
The patch titled
Subject: mm/huge_memory.c: fix data loss when splitting a file pmd
has been added to the -mm tree. Its filename is
thp-fix-data-loss-when-splitting-a-file-pmd.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/thp-fix-data-loss-when-splitting-a…
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/thp-fix-data-loss-when-splitting-a…
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Hugh Dickins <hughd(a)google.com>
Subject: mm/huge_memory.c: fix data loss when splitting a file pmd
__split_huge_pmd_locked() must check if the cleared huge pmd was dirty,
and propagate that to PageDirty: otherwise, data may be lost when a huge
tmpfs page is modified then split then reclaimed.
How has this taken so long to be noticed? Because there was no problem
when the huge page is written by a write system call (shmem_write_end()
calls set_page_dirty()), nor when the page is allocated for a write fault
(fault_dirty_shared_page() calls set_page_dirty()); but when allocated for
a read fault (which MAP_POPULATE simulates), no set_page_dirty().
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.1807111741430.1106@eggly.anvils
Fixes: d21b9e57c74c ("thp: handle file pages in split_huge_pmd()")
Signed-off-by: Hugh Dickins <hughd(a)google.com>
Reported-by: Ashwin Chaugule <ashwinch(a)google.com>
Reviewed-by: Yang Shi <yang.shi(a)linux.alibaba.com>
Reviewed-by: Kirill A. Shutemov <kirill.shutemov(a)linux.intel.com>
Cc: "Huang, Ying" <ying.huang(a)intel.com>
Cc: <stable(a)vger.kernel.org> [4.8+]
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
mm/huge_memory.c | 2 ++
1 file changed, 2 insertions(+)
diff -puN mm/huge_memory.c~thp-fix-data-loss-when-splitting-a-file-pmd mm/huge_memory.c
--- a/mm/huge_memory.c~thp-fix-data-loss-when-splitting-a-file-pmd
+++ a/mm/huge_memory.c
@@ -2084,6 +2084,8 @@ static void __split_huge_pmd_locked(stru
if (vma_is_dax(vma))
return;
page = pmd_page(_pmd);
+ if (!PageDirty(page) && pmd_dirty(_pmd))
+ set_page_dirty(page);
if (!PageReferenced(page) && pmd_young(_pmd))
SetPageReferenced(page);
page_remove_rmap(page, true);
_
Patches currently in -mm which might be from hughd(a)google.com are
thp-fix-data-loss-when-splitting-a-file-pmd.patch
The patch titled
Subject: fat: fix memory allocation failure handling of match_strdup()
has been added to the -mm tree. Its filename is
fat-fix-memory-allocation-failure-handling-of-match_strdup.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/fat-fix-memory-allocation-failure-…
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/fat-fix-memory-allocation-failure-…
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: OGAWA Hirofumi <hirofumi(a)mail.parknet.co.jp>
Subject: fat: fix memory allocation failure handling of match_strdup()
In parse_options(), if match_strdup() failed, parse_options() leaves
opts->iocharset in unexpected state (i.e. still pointing the freed
string). And this can be the cause of double free.
To fix, this initialize opts->iocharset always when freeing.
Link: http://lkml.kernel.org/r/8736wp9dzc.fsf@mail.parknet.co.jp
Signed-off-by: OGAWA Hirofumi <hirofumi(a)mail.parknet.co.jp>
Reported-by: syzbot+90b8e10515ae88228a92(a)syzkaller.appspotmail.com
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
fs/fat/inode.c | 20 +++++++++++++-------
1 file changed, 13 insertions(+), 7 deletions(-)
diff -puN fs/fat/inode.c~fat-fix-memory-allocation-failure-handling-of-match_strdup fs/fat/inode.c
--- a/fs/fat/inode.c~fat-fix-memory-allocation-failure-handling-of-match_strdup
+++ a/fs/fat/inode.c
@@ -707,13 +707,21 @@ static void fat_set_state(struct super_b
brelse(bh);
}
+static void fat_reset_iocharset(struct fat_mount_options *opts)
+{
+ if (opts->iocharset != fat_default_iocharset) {
+ /* Note: opts->iocharset can be NULL here */
+ kfree(opts->iocharset);
+ opts->iocharset = fat_default_iocharset;
+ }
+}
+
static void delayed_free(struct rcu_head *p)
{
struct msdos_sb_info *sbi = container_of(p, struct msdos_sb_info, rcu);
unload_nls(sbi->nls_disk);
unload_nls(sbi->nls_io);
- if (sbi->options.iocharset != fat_default_iocharset)
- kfree(sbi->options.iocharset);
+ fat_reset_iocharset(&sbi->options);
kfree(sbi);
}
@@ -1132,7 +1140,7 @@ static int parse_options(struct super_bl
opts->fs_fmask = opts->fs_dmask = current_umask();
opts->allow_utime = -1;
opts->codepage = fat_default_codepage;
- opts->iocharset = fat_default_iocharset;
+ fat_reset_iocharset(opts);
if (is_vfat) {
opts->shortname = VFAT_SFN_DISPLAY_WINNT|VFAT_SFN_CREATE_WIN95;
opts->rodir = 0;
@@ -1289,8 +1297,7 @@ static int parse_options(struct super_bl
/* vfat specific */
case Opt_charset:
- if (opts->iocharset != fat_default_iocharset)
- kfree(opts->iocharset);
+ fat_reset_iocharset(opts);
iocharset = match_strdup(&args[0]);
if (!iocharset)
return -ENOMEM;
@@ -1881,8 +1888,7 @@ out_fail:
iput(fat_inode);
unload_nls(sbi->nls_io);
unload_nls(sbi->nls_disk);
- if (sbi->options.iocharset != fat_default_iocharset)
- kfree(sbi->options.iocharset);
+ fat_reset_iocharset(&sbi->options);
sb->s_fs_info = NULL;
kfree(sbi);
return error;
_
Patches currently in -mm which might be from hirofumi(a)mail.parknet.co.jp are
fat-fix-memory-allocation-failure-handling-of-match_strdup.patch
This fixes some nasty issues I found in nouveau that were being caused
looping through connectors using racy legacy methods, along with some
caused by making incorrect assumptions about the drm_connector structs
in nouveau's connector list. Most of these memory corruption issues
could be reproduced by using an MST hub with nouveau.
Cc: Karol Herbst <karolherbst(a)gmail.com>
Cc: stable(a)vger.kernel.org
Lyude Paul (2):
drm/nouveau: Use drm_connector_list_iter_* for iterating ues connectors
drm/nouveau: Avoid looping through fake MST connectors
drivers/gpu/drm/nouveau/nouveau_backlight.c | 6 ++--
drivers/gpu/drm/nouveau/nouveau_connector.c | 9 ++++--
drivers/gpu/drm/nouveau/nouveau_connector.h | 36 ++++++++++++++++++---
drivers/gpu/drm/nouveau/nouveau_display.c | 10 ++++--
4 files changed, 51 insertions(+), 10 deletions(-)
--
2.17.1
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We are a team, we can process 300+ images per day for you.
If you need any image editing, please let us know.
Photos cut out;
Photos clipping path;
Photos masking;
Photo shadow creation;
Photos retouching;
Beauty Model retouching on skin, face, body;
Glamour retouching;
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The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 92748beac07c471d995fbec642b63572dc01b3dc Mon Sep 17 00:00:00 2001
From: Stefan Agner <stefan(a)agner.ch>
Date: Wed, 4 Jul 2018 17:07:45 +0200
Subject: [PATCH] mmc: sdhci-esdhc-imx: allow 1.8V modes without 100/200MHz
pinctrl states
If pinctrl nodes for 100/200MHz are missing, the controller should
not select any mode which need signal frequencies 100MHz or higher.
To prevent such speed modes the driver currently uses the quirk flag
SDHCI_QUIRK2_NO_1_8_V. This works nicely for SD cards since 1.8V
signaling is required for all faster modes and slower modes use 3.3V
signaling only.
However, there are eMMC modes which use 1.8V signaling and run below
100MHz, e.g. DDR52 at 1.8V. With using SDHCI_QUIRK2_NO_1_8_V this
mode is prevented. When using a fixed 1.8V regulator as vqmmc-supply
the stack has no valid mode to use. In this tenuous situation the
kernel continuously prints voltage switching errors:
mmc1: Switching to 3.3V signalling voltage failed
Avoid using SDHCI_QUIRK2_NO_1_8_V and prevent faster modes by
altering the SDHCI capability register. With that the stack is able
to select 1.8V modes even if no faster pinctrl states are available:
# cat /sys/kernel/debug/mmc1/ios
...
timing spec: 8 (mmc DDR52)
signal voltage: 1 (1.80 V)
...
Link: http://lkml.kernel.org/r/20180628081331.13051-1-stefan@agner.ch
Signed-off-by: Stefan Agner <stefan(a)agner.ch>
Fixes: ad93220de7da ("mmc: sdhci-esdhc-imx: change pinctrl state according
to uhs mode")
Cc: <stable(a)vger.kernel.org> # v4.13+
Signed-off-by: Ulf Hansson <ulf.hansson(a)linaro.org>
diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c
index d6aef70d34fa..4eb3d29ecde1 100644
--- a/drivers/mmc/host/sdhci-esdhc-imx.c
+++ b/drivers/mmc/host/sdhci-esdhc-imx.c
@@ -312,6 +312,15 @@ static u32 esdhc_readl_le(struct sdhci_host *host, int reg)
if (imx_data->socdata->flags & ESDHC_FLAG_HS400)
val |= SDHCI_SUPPORT_HS400;
+
+ /*
+ * Do not advertise faster UHS modes if there are no
+ * pinctrl states for 100MHz/200MHz.
+ */
+ if (IS_ERR_OR_NULL(imx_data->pins_100mhz) ||
+ IS_ERR_OR_NULL(imx_data->pins_200mhz))
+ val &= ~(SDHCI_SUPPORT_SDR50 | SDHCI_SUPPORT_DDR50
+ | SDHCI_SUPPORT_SDR104 | SDHCI_SUPPORT_HS400);
}
}
@@ -1158,18 +1167,6 @@ sdhci_esdhc_imx_probe_dt(struct platform_device *pdev,
ESDHC_PINCTRL_STATE_100MHZ);
imx_data->pins_200mhz = pinctrl_lookup_state(imx_data->pinctrl,
ESDHC_PINCTRL_STATE_200MHZ);
- if (IS_ERR(imx_data->pins_100mhz) ||
- IS_ERR(imx_data->pins_200mhz)) {
- dev_warn(mmc_dev(host->mmc),
- "could not get ultra high speed state, work on normal mode\n");
- /*
- * fall back to not supporting uhs by specifying no
- * 1.8v quirk
- */
- host->quirks2 |= SDHCI_QUIRK2_NO_1_8_V;
- }
- } else {
- host->quirks2 |= SDHCI_QUIRK2_NO_1_8_V;
}
/* call to generic mmc_of_parse to support additional capabilities */