From mboxrd@z Thu Jan 1 00:00:00 1970 From: pavel@ucw.cz (Pavel Machek) Date: Sat, 14 Nov 2015 21:26:24 +0100 Subject: [PATCH v2 10/11] PM / Hibernate: clean cached pages on architectures that require it In-Reply-To: <1445966960-31724-11-git-send-email-james.morse@arm.com> References: <1445966960-31724-1-git-send-email-james.morse@arm.com> <1445966960-31724-11-git-send-email-james.morse@arm.com> Message-ID: <20151114202623.GC20429@amd> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tue 2015-10-27 17:29:19, James Morse wrote: > Some architectures require code written to memory as if it were data to be > 'cleaned' from any data caches so that the processor can fetch them as new > instructions. > > During resume from hibernate, the snapshot code copies some pages directly, > meaning these architectures do not get a chance to perform their cache > maintenance. Add a call to flush_icache_range(), which is provided by > architectures that require it, to perform the maintenance. > > This mirrors the kernel's behaviour when loading kernel modules and when > mapping executable pages to user space. > > Signed-off-by: James Morse Looks reasonable. Acked-by: Pavel Machek > --- > kernel/power/snapshot.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c > index 5235dd4e1e2f..139fc449ad75 100644 > --- a/kernel/power/snapshot.c > +++ b/kernel/power/snapshot.c > @@ -1196,9 +1197,12 @@ static unsigned int count_data_pages(void) > static inline void do_copy_page(long *dst, long *src) > { > int n; > + unsigned long __maybe_unused start = (unsigned long)dst; Why the "maybe unused"? > for (n = PAGE_SIZE / sizeof(long); n; n--) > *dst++ = *src++; > + > + flush_icache_range(start, start+PAGE_SIZE); > } Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html