Messages in this thread | | | From | Evan Green <> | Date | Mon, 15 Nov 2021 09:12:47 -0800 | Subject | Re: [PATCH] PM / hibernate: Fix snapshot partial write lengths |
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Gentle bump.
On Fri, Oct 29, 2021 at 12:24 PM Evan Green <evgreen@chromium.org> wrote: > > 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 <evgreen@chromium.org> > --- > > 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 740723bb388524..ad241b4ff64c58 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)) { > -- > 2.31.0 >
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