From cefcf24b4d351daf70ecd945324e200d3736821e Mon Sep 17 00:00:00 2001 From: Thomas Zeitlhofer Date: Tue, 23 Nov 2021 20:18:43 +0100 Subject: [PATCH 1/2] PM: hibernate: use correct mode for swsusp_close() Commit 39fbef4b0f77 ("PM: hibernate: Get block device exclusively in swsusp_check()") changed the opening mode of the block device to (FMODE_READ | FMODE_EXCL). In the corresponding calls to swsusp_close(), the mode is still just FMODE_READ which triggers the warning in blkdev_flush_mapping() on resume from hibernate. So, use the mode (FMODE_READ | FMODE_EXCL) also when closing the device. Fixes: 39fbef4b0f77 ("PM: hibernate: Get block device exclusively in swsusp_check()") Signed-off-by: Thomas Zeitlhofer Signed-off-by: Rafael J. Wysocki --- kernel/power/hibernate.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index 9ed9b744876c1..e6af502c2fd77 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -693,7 +693,7 @@ static int load_image_and_restore(void) goto Unlock; error = swsusp_read(&flags); - swsusp_close(FMODE_READ); + swsusp_close(FMODE_READ | FMODE_EXCL); if (!error) error = hibernation_restore(flags & SF_PLATFORM_MODE); @@ -983,7 +983,7 @@ static int software_resume(void) /* The snapshot device should not be opened while we're running */ if (!hibernate_acquire()) { error = -EBUSY; - swsusp_close(FMODE_READ); + swsusp_close(FMODE_READ | FMODE_EXCL); goto Unlock; } @@ -1018,7 +1018,7 @@ static int software_resume(void) pm_pr_dbg("Hibernation image not present or could not be loaded.\n"); return error; Close_Finish: - swsusp_close(FMODE_READ); + swsusp_close(FMODE_READ | FMODE_EXCL); goto Finish; } From 88a5045f176b78c33a269a30a7b146e99c550bd9 Mon Sep 17 00:00:00 2001 From: Evan Green Date: Fri, 29 Oct 2021 12:24:22 -0700 Subject: [PATCH 2/2] PM: hibernate: Fix snapshot partial write lengths snapshot_write() is inappropriately limiting the amount of data that can be written in cases where a partial page has already been written. For example, one would expect to be able to write 1 byte, then 4095 bytes to the snapshot device, and have both of those complete fully (since now we're aligned to a page again). But what ends up happening is we write 1 byte, then 4094/4095 bytes complete successfully. The reason is that simple_write_to_buffer()'s second argument is the total size of the buffer, not the size of the buffer minus the offset. Since simple_write_to_buffer() accounts for the offset in its implementation, snapshot_write() can just pass the full page size directly down. Signed-off-by: Evan Green Signed-off-by: Rafael J. Wysocki --- kernel/power/user.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/power/user.c b/kernel/power/user.c index 740723bb38852..ad241b4ff64c5 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -177,7 +177,7 @@ static ssize_t snapshot_write(struct file *filp, const char __user *buf, if (res <= 0) goto unlock; } else { - res = PAGE_SIZE - pg_offp; + res = PAGE_SIZE; } if (!data_of(data->handle)) {