Re: [PATCH v7 12/15] sh: Drop cache flush of the zero page at boot
Mike Rapoport <[email protected]> Sat, 30 May 2026 19:19:36 +0300
| Newsgroups | org.kernel.vger.linux-sh,org.infradead.lists.linux-arm-kernel,org.kernel.vger.linux-hardening,org.kernel.vger.linux-kernel,org.kvack.linux-mm,org.ozlabs.lists.linuxppc-dev |
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| Message-ID | <[email protected]> |
On Fri, May 29, 2026 at 05:02:03PM +0200, Ard Biesheuvel wrote: > From: Ard Biesheuvel <[email protected]> > > SuperH performs cache maintenance on the zero page during boot, > presumably because before commit > > 6215d9f4470f ("arch, mm: consolidate empty_zero_page") > > the zero page did double duty as a boot params region, and was cleared > separately, as it was not part of BSS. The memset() in question was > dropped by that commit, but the __flush_wback_region() call remained. > > As empty_zero_page[] has been moved to BSS, it can be treated as any > other BSS memory, and so the cache flush can be dropped. > > Cc: Yoshinori Sato <[email protected]> > Cc: Rich Felker <[email protected]> > Cc: John Paul Adrian Glaubitz <[email protected]> > Cc: Mike Rapoport <[email protected]> > Cc: Geert Uytterhoeven <[email protected]> > Signed-off-by: Ard Biesheuvel <[email protected]> Acked-by: Mike Rapoport (Microsoft) <[email protected]> > --- > arch/sh/mm/init.c | 3 --- > 1 file changed, 3 deletions(-) -- Sincerely yours, Mike.