When fallocate() is used on a shmem file, the pages we allocate can end
up with !PageUptodate.
Since UFFDIO_CONTINUE tries to find the existing page the user wants to
map with SGP_READ, we would fail to find such a page, since
shmem_getpage_gfp returns with a "NULL" pagep for SGP_READ if it
discovers !PageUptodate. As a result, UFFDIO_CONTINUE returns -EFAULT,
as it would do if the page wasn't found in the page cache at all.
This isn't the intended behavior. UFFDIO_CONTINUE is just trying to find
if a page exists, and doesn't care whether it still needs to be cleared
or not. So, instead of SGP_READ, pass in SGP_NOALLOC. This is the same,
except for one critical difference: in the !PageUptodate case,
SGP_NOALLOC will clear the page and then return it. With this change,
UFFDIO_CONTINUE works properly (succeeds) on a shmem file which has been
fallocated, but otherwise not modified.
Fixes: 153132571f02 ("userfaultfd/shmem: support UFFDIO_CONTINUE for shmem")
Cc: stable(a)vger.kernel.org
Signed-off-by: Axel Rasmussen <axelrasmussen(a)google.com>
---
mm/userfaultfd.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c
index 4f4892a5f767..07d3befc80e4 100644
--- a/mm/userfaultfd.c
+++ b/mm/userfaultfd.c
@@ -246,7 +246,10 @@ static int mcontinue_atomic_pte(struct mm_struct *dst_mm,
struct page *page;
int ret;
- ret = shmem_getpage(inode, pgoff, &page, SGP_READ);
+ ret = shmem_getpage(inode, pgoff, &page, SGP_NOALLOC);
+ /* Our caller expects us to return -EFAULT if we failed to find page. */
+ if (ret == -ENOENT)
+ ret = -EFAULT;
if (ret)
goto out;
if (!page) {
--
2.36.1.476.g0c4daa206d-goog
When fallocate() is used on a shmem file, the pages we allocate can end
up with !PageUptodate.
Since UFFDIO_CONTINUE tries to find the existing page the user wants to
map with SGP_READ, we would fail to find such a page, since
shmem_getpage_gfp returns with a "NULL" pagep for SGP_READ if it
discovers !PageUptodate. As a result, UFFDIO_CONTINUE returns -EFAULT,
as it would do if the page wasn't found in the page cache at all.
This isn't the intended behavior. UFFDIO_CONTINUE is just trying to find
if a page exists, and doesn't care whether it still needs to be cleared
or not. So, instead of SGP_READ, pass in SGP_NOALLOC. This is the same,
except for one critical difference: in the !PageUptodate case,
SGP_NOALLOC will clear the page and then return it. With this change,
UFFDIO_CONTINUE works properly (succeeds) on a shmem file which has been
fallocated, but otherwise not modified.
Fixes: 153132571f02 ("userfaultfd/shmem: support UFFDIO_CONTINUE for shmem")
Cc: stable(a)vger.kernel.org
Signed-off-by: Axel Rasmussen <axelrasmussen(a)google.com>
---
mm/userfaultfd.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c
index 4f4892a5f767..c156f7f5b854 100644
--- a/mm/userfaultfd.c
+++ b/mm/userfaultfd.c
@@ -246,7 +246,7 @@ static int mcontinue_atomic_pte(struct mm_struct *dst_mm,
struct page *page;
int ret;
- ret = shmem_getpage(inode, pgoff, &page, SGP_READ);
+ ret = shmem_getpage(inode, pgoff, &page, SGP_NOALLOC);
if (ret)
goto out;
if (!page) {
--
2.36.1.255.ge46751e96f-goog
This is a preparation patch for the S29GL064N buffer writes fix. There
is no functional change.
Link: https://lore.kernel.org/r/b687c259-6413-26c9-d4c9-b3afa69ea124@pengutronix.…
Fixes: dfeae1073583("mtd: cfi_cmdset_0002: Change write buffer to check correct value")
Signed-off-by: Tokunori Ikegami <ikegami.t(a)gmail.com>
Cc: stable(a)vger.kernel.org
Acked-by: Vignesh Raghavendra <vigneshr(a)ti.com>
Signed-off-by: Miquel Raynal <miquel.raynal(a)bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20220323170458.5608-2-ikegami.t@gmail.com
---
drivers/mtd/chips/cfi_cmdset_0002.c | 77 ++++++++++++-----------------
1 file changed, 32 insertions(+), 45 deletions(-)
diff --git a/drivers/mtd/chips/cfi_cmdset_0002.c b/drivers/mtd/chips/cfi_cmdset_0002.c
index 870d1f1331b1..a8e1a961e844 100644
--- a/drivers/mtd/chips/cfi_cmdset_0002.c
+++ b/drivers/mtd/chips/cfi_cmdset_0002.c
@@ -730,50 +730,34 @@ static struct mtd_info *cfi_amdstd_setup(struct mtd_info *mtd)
}
/*
- * Return true if the chip is ready.
+ * Return true if the chip is ready and has the correct value.
*
* Ready is one of: read mode, query mode, erase-suspend-read mode (in any
* non-suspended sector) and is indicated by no toggle bits toggling.
*
+ * Error are indicated by toggling bits or bits held with the wrong value,
+ * or with bits toggling.
+ *
* Note that anything more complicated than checking if no bits are toggling
* (including checking DQ5 for an error status) is tricky to get working
* correctly and is therefore not done (particularly with interleaved chips
* as each chip must be checked independently of the others).
*/
-static int __xipram chip_ready(struct map_info *map, unsigned long addr)
+static int __xipram chip_ready(struct map_info *map, unsigned long addr,
+ map_word *expected)
{
map_word d, t;
+ int ret;
d = map_read(map, addr);
t = map_read(map, addr);
- return map_word_equal(map, d, t);
-}
+ ret = map_word_equal(map, d, t);
-/*
- * Return true if the chip is ready and has the correct value.
- *
- * Ready is one of: read mode, query mode, erase-suspend-read mode (in any
- * non-suspended sector) and it is indicated by no bits toggling.
- *
- * Error are indicated by toggling bits or bits held with the wrong value,
- * or with bits toggling.
- *
- * Note that anything more complicated than checking if no bits are toggling
- * (including checking DQ5 for an error status) is tricky to get working
- * correctly and is therefore not done (particularly with interleaved chips
- * as each chip must be checked independently of the others).
- *
- */
-static int __xipram chip_good(struct map_info *map, unsigned long addr, map_word expected)
-{
- map_word oldd, curd;
-
- oldd = map_read(map, addr);
- curd = map_read(map, addr);
+ if (!ret || !expected)
+ return ret;
- return map_word_equal(map, oldd, curd) &&
- map_word_equal(map, curd, expected);
+ return map_word_equal(map, t, *expected);
}
static int get_chip(struct map_info *map, struct flchip *chip, unsigned long adr, int mode)
@@ -790,7 +774,7 @@ static int get_chip(struct map_info *map, struct flchip *chip, unsigned long adr
case FL_STATUS:
for (;;) {
- if (chip_ready(map, adr))
+ if (chip_ready(map, adr, NULL))
break;
if (time_after(jiffies, timeo)) {
@@ -828,7 +812,7 @@ static int get_chip(struct map_info *map, struct flchip *chip, unsigned long adr
chip->state = FL_ERASE_SUSPENDING;
chip->erase_suspended = 1;
for (;;) {
- if (chip_ready(map, adr))
+ if (chip_ready(map, adr, NULL))
break;
if (time_after(jiffies, timeo)) {
@@ -1361,7 +1345,7 @@ static int do_otp_lock(struct map_info *map, struct flchip *chip, loff_t adr,
/* wait for chip to become ready */
timeo = jiffies + msecs_to_jiffies(2);
for (;;) {
- if (chip_ready(map, adr))
+ if (chip_ready(map, adr, NULL))
break;
if (time_after(jiffies, timeo)) {
@@ -1628,10 +1612,11 @@ static int __xipram do_write_oneword(struct map_info *map, struct flchip *chip,
}
/*
- * We check "time_after" and "!chip_good" before checking
- * "chip_good" to avoid the failure due to scheduling.
+ * We check "time_after" and "!chip_ready" before checking
+ * "chip_ready" to avoid the failure due to scheduling.
*/
- if (time_after(jiffies, timeo) && !chip_good(map, adr, datum)) {
+ if (time_after(jiffies, timeo) &&
+ !chip_ready(map, adr, &datum)) {
xip_enable(map, chip, adr);
printk(KERN_WARNING "MTD %s(): software timeout\n", __func__);
xip_disable(map, chip, adr);
@@ -1639,7 +1624,7 @@ static int __xipram do_write_oneword(struct map_info *map, struct flchip *chip,
break;
}
- if (chip_good(map, adr, datum))
+ if (chip_ready(map, adr, &datum))
break;
/* Latency issues. Drop the lock, wait a while and retry */
@@ -1883,13 +1868,13 @@ static int __xipram do_write_buffer(struct map_info *map, struct flchip *chip,
}
/*
- * We check "time_after" and "!chip_good" before checking "chip_good" to avoid
- * the failure due to scheduling.
+ * We check "time_after" and "!chip_ready" before checking
+ * "chip_ready" to avoid the failure due to scheduling.
*/
- if (time_after(jiffies, timeo) && !chip_good(map, adr, datum))
+ if (time_after(jiffies, timeo) && !chip_ready(map, adr, &datum))
break;
- if (chip_good(map, adr, datum)) {
+ if (chip_ready(map, adr, &datum)) {
xip_enable(map, chip, adr);
goto op_done;
}
@@ -2023,7 +2008,7 @@ static int cfi_amdstd_panic_wait(struct map_info *map, struct flchip *chip,
* If the driver thinks the chip is idle, and no toggle bits
* are changing, then the chip is actually idle for sure.
*/
- if (chip->state == FL_READY && chip_ready(map, adr))
+ if (chip->state == FL_READY && chip_ready(map, adr, NULL))
return 0;
/*
@@ -2040,7 +2025,7 @@ static int cfi_amdstd_panic_wait(struct map_info *map, struct flchip *chip,
/* wait for the chip to become ready */
for (i = 0; i < jiffies_to_usecs(timeo); i++) {
- if (chip_ready(map, adr))
+ if (chip_ready(map, adr, NULL))
return 0;
udelay(1);
@@ -2104,13 +2089,13 @@ static int do_panic_write_oneword(struct map_info *map, struct flchip *chip,
map_write(map, datum, adr);
for (i = 0; i < jiffies_to_usecs(uWriteTimeout); i++) {
- if (chip_ready(map, adr))
+ if (chip_ready(map, adr, NULL))
break;
udelay(1);
}
- if (!chip_good(map, adr, datum)) {
+ if (!chip_ready(map, adr, &datum)) {
/* reset on all failures. */
map_write(map, CMD(0xF0), chip->start);
/* FIXME - should have reset delay before continuing */
@@ -2251,6 +2236,7 @@ static int __xipram do_erase_chip(struct map_info *map, struct flchip *chip)
DECLARE_WAITQUEUE(wait, current);
int ret = 0;
int retry_cnt = 0;
+ map_word datum = map_word_ff(map);
adr = cfi->addr_unlock1;
@@ -2305,7 +2291,7 @@ static int __xipram do_erase_chip(struct map_info *map, struct flchip *chip)
chip->erase_suspended = 0;
}
- if (chip_good(map, adr, map_word_ff(map)))
+ if (chip_ready(map, adr, &datum))
break;
if (time_after(jiffies, timeo)) {
@@ -2347,6 +2333,7 @@ static int __xipram do_erase_oneblock(struct map_info *map, struct flchip *chip,
DECLARE_WAITQUEUE(wait, current);
int ret = 0;
int retry_cnt = 0;
+ map_word datum = map_word_ff(map);
adr += chip->start;
@@ -2401,7 +2388,7 @@ static int __xipram do_erase_oneblock(struct map_info *map, struct flchip *chip,
chip->erase_suspended = 0;
}
- if (chip_good(map, adr, map_word_ff(map))) {
+ if (chip_ready(map, adr, &datum)) {
xip_enable(map, chip, adr);
break;
}
@@ -2616,7 +2603,7 @@ static int __maybe_unused do_ppb_xxlock(struct map_info *map,
*/
timeo = jiffies + msecs_to_jiffies(2000); /* 2s max (un)locking */
for (;;) {
- if (chip_ready(map, adr))
+ if (chip_ready(map, adr, NULL))
break;
if (time_after(jiffies, timeo)) {
--
2.34.1
Invalidating the buffer memory in arch_sync_dma_for_device() for
FROM_DEVICE transfers
When using the streaming DMA API to map a buffer prior to inbound
non-coherent DMA (i.e. DMA_FROM_DEVICE), we invalidate any dirty CPU
cachelines so that they will not be written back during the transfer and
corrupt the buffer contents written by the DMA. This, however, poses two
potential problems:
(1) If the DMA transfer does not write to every byte in the buffer,
then the unwritten bytes will contain stale data once the transfer
has completed.
(2) If the buffer has a virtual alias in userspace, then stale data
may be visible via this alias during the period between performing
the cache invalidation and the DMA writes landing in memory.
Address both of these issues by cleaning (aka writing-back) the dirty
lines in arch_sync_dma_for_device(DMA_FROM_DEVICE) instead of discarding
them using invalidation.
Cc: Ard Biesheuvel <ardb(a)kernel.org>
Cc: Christoph Hellwig <hch(a)lst.de>
Cc: Catalin Marinas <catalin.marinas(a)arm.com>
Cc: Robin Murphy <robin.murphy(a)arm.com>
Cc: Russell King <linux(a)armlinux.org.uk>
Cc: <stable(a)vger.kernel.org>
Link: https://lore.kernel.org/r/20220606152150.GA31568@willie-the-truck
Signed-off-by: Will Deacon <will(a)kernel.org>
---
arch/arm64/mm/cache.S | 2 --
1 file changed, 2 deletions(-)
diff --git a/arch/arm64/mm/cache.S b/arch/arm64/mm/cache.S
index 0ea6cc25dc66..21c907987080 100644
--- a/arch/arm64/mm/cache.S
+++ b/arch/arm64/mm/cache.S
@@ -218,8 +218,6 @@ SYM_FUNC_ALIAS(__dma_flush_area, __pi___dma_flush_area)
*/
SYM_FUNC_START(__pi___dma_map_area)
add x1, x0, x1
- cmp w2, #DMA_FROM_DEVICE
- b.eq __pi_dcache_inval_poc
b __pi_dcache_clean_poc
SYM_FUNC_END(__pi___dma_map_area)
SYM_FUNC_ALIAS(__dma_map_area, __pi___dma_map_area)
--
2.36.1.476.g0c4daa206d-goog
gbaudio_dapm_free_controls() iterates over widgets using the
list_for_each_entry*() family of macros from <linux/list.h>, which
leaves the loop cursor pointing to a meaningless structure if it
completes a traversal of the list. The cursor was set to NULL at the end
of the loop body, but would be overwritten by the final loop cursor
update.
Because of this behavior, the widget could be non-null after the loop
even if the widget wasn't found, and the cleanup logic would treat the
pointer as a valid widget to free.
To fix this, introduce a temporary variable to act as the loop cursor
and copy it to a variable that can be accessed after the loop finishes.
Due to not removing any list elements, use list_for_each_entry() instead
of list_for_each_entry_safe() in the revised loop.
This was detected with the help of Coccinelle.
Fixes: 510e340efe0c ("staging: greybus: audio: Add helper APIs for dynamic audio modules")
Cc: stable(a)vger.kernel.org
Reviewed-by: Dan Carpenter <dan.carpenter(a)oracle.com>
Reviewed-by: Johan Hovold <johan(a)kernel.org>
Signed-off-by: Jared Kangas <kangas.jd(a)gmail.com>
---
Changes since v1:
* Removed safe list iteration as suggested by Johan Hovold <johan(a)kernel.org>
* Updated patch changelog to explain the list iteration change
* Added tags to changelog based on feedback (Cc:, Fixes:, Reviewed-by:)
drivers/staging/greybus/audio_helper.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/drivers/staging/greybus/audio_helper.c b/drivers/staging/greybus/audio_helper.c
index 843760675876..05e91e6bc2a0 100644
--- a/drivers/staging/greybus/audio_helper.c
+++ b/drivers/staging/greybus/audio_helper.c
@@ -115,7 +115,7 @@ int gbaudio_dapm_free_controls(struct snd_soc_dapm_context *dapm,
int num)
{
int i;
- struct snd_soc_dapm_widget *w, *next_w;
+ struct snd_soc_dapm_widget *w, *tmp_w;
#ifdef CONFIG_DEBUG_FS
struct dentry *parent = dapm->debugfs_dapm;
struct dentry *debugfs_w = NULL;
@@ -124,13 +124,13 @@ int gbaudio_dapm_free_controls(struct snd_soc_dapm_context *dapm,
mutex_lock(&dapm->card->dapm_mutex);
for (i = 0; i < num; i++) {
/* below logic can be optimized to identify widget pointer */
- list_for_each_entry_safe(w, next_w, &dapm->card->widgets,
- list) {
- if (w->dapm != dapm)
- continue;
- if (!strcmp(w->name, widget->name))
+ w = NULL;
+ list_for_each_entry(tmp_w, &dapm->card->widgets, list) {
+ if (tmp_w->dapm == dapm &&
+ !strcmp(tmp_w->name, widget->name)) {
+ w = tmp_w;
break;
- w = NULL;
+ }
}
if (!w) {
dev_err(dapm->dev, "%s: widget not found\n",
--
2.34.3