Re: [PATCH] vdso/datastore: Zero out newly allocated datastore pages

[Thomas Weißschuh]

Hi,

please disregard this patch...

On Thu, Apr 09, 2026 at 01:14:05PM +0200, Thomas Weißschuh wrote:
> The data pages need to be zeroed initially, as garbage data can break
> the vDSO userspace logic.
> 
> Fixes: 05988dba1179 ("vdso/datastore: Allocate data pages dynamically")
> Link: https://lore.kernel.org/lkml/aQjJNmwniQwwjeBR@xxxxxxxxxxxxxxxxxxxxxxxx/
> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@xxxxxxxxxxxxx>
> ---
> I messed up and dropped __GFP_ZERO again when switching from folio_alloc() to
> alloc_pages() in v6 of "sparc64: vdso: Switch to the generic vDSO library"
> Previously the missing __GFP_ZERO triggered boot-failures in -next, but
> apparently with alloc_pages() we got "lucky" so far.

... I panicked a bit after looking at the code again and not seeing the
explicit zeroing.  The actually works fine, as the memcpy() from the static
vdso_initdata will do the zeroing.

Sorry for the noise.


Thomas