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authorArnd Bergmann <arnd@arndb.de>2012-01-07 11:51:28 +0000
committerArnd Bergmann <arnd@arndb.de>2012-01-07 11:51:28 +0000
commit40ba95fdf158713377d47736b1b3a9d75f4f2515 (patch)
tree17a3216542d1107f777fd82577c91aebbce597d6 /drivers/oprofile/oprofilefs.c
parent70d84a6431d732cbc4e68e72b6890cdd3865d43d (diff)
parent0575fb754dbfc32a01f297e778533340a533ec68 (diff)
Merge branch 'depends/rmk/restart' into next/cleanup
Conflicts: arch/arm/mach-at91/at91cap9.c arch/arm/mach-at91/at91sam9260.c arch/arm/mach-at91/at91sam9261.c arch/arm/mach-at91/at91sam9263.c arch/arm/mach-at91/at91sam9g45.c arch/arm/mach-at91/at91sam9rl.c arch/arm/mach-exynos/cpu.c arch/arm/mach-shmobile/board-kota2.c This resolves a bunch of conflicts between the arm-soc tree and changes from the arm tree that have gone upstream. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'drivers/oprofile/oprofilefs.c')
-rw-r--r--drivers/oprofile/oprofilefs.c11
1 files changed, 9 insertions, 2 deletions
diff --git a/drivers/oprofile/oprofilefs.c b/drivers/oprofile/oprofilefs.c
index d0de6cc2d7a..2f0aa0f700e 100644
--- a/drivers/oprofile/oprofilefs.c
+++ b/drivers/oprofile/oprofilefs.c
@@ -60,6 +60,13 @@ ssize_t oprofilefs_ulong_to_user(unsigned long val, char __user *buf, size_t cou
}
+/*
+ * Note: If oprofilefs_ulong_from_user() returns 0, then *val remains
+ * unchanged and might be uninitialized. This follows write syscall
+ * implementation when count is zero: "If count is zero ... [and if]
+ * no errors are detected, 0 will be returned without causing any
+ * other effect." (man 2 write)
+ */
int oprofilefs_ulong_from_user(unsigned long *val, char const __user *buf, size_t count)
{
char tmpbuf[TMPBUFSIZE];
@@ -79,7 +86,7 @@ int oprofilefs_ulong_from_user(unsigned long *val, char const __user *buf, size_
raw_spin_lock_irqsave(&oprofilefs_lock, flags);
*val = simple_strtoul(tmpbuf, NULL, 0);
raw_spin_unlock_irqrestore(&oprofilefs_lock, flags);
- return 0;
+ return count;
}
@@ -99,7 +106,7 @@ static ssize_t ulong_write_file(struct file *file, char const __user *buf, size_
return -EINVAL;
retval = oprofilefs_ulong_from_user(&value, buf, count);
- if (retval)
+ if (retval <= 0)
return retval;
retval = oprofile_set_ulong(file->private_data, value);