Sumit Garg wrote: > On Sat, 4 Feb 2023 at 09:36, Ira Weiny <ira.weiny@xxxxxxxxx> wrote: > > > > Sumit, > > > > I did not see a follow up on this series per your last email.[1] I'd like to > > move forward with getting rid of kmap_to_page(). So Hopefully this can land > > and you can build on this rather than the other way around? > > Apologies Ira for keeping you waiting. Actually I was fully involved > with other high priority work with my upstream review backlog > increasing. So I wasn't able to devote time to this work. Sure I will > rebase my work on top of your changes. No problem on my end. I just wanted to ensure that I did not miss something. Thanks for the reviews! Ira > > -Sumit > > > > > All, > > > > Al Viro found[2] that kmap_to_page() is broken. But not only is it broken, it > > presents confusion over how highmem should be used because kmap() and friends > > should not be used for 'long term' mappings. > > > > get_kernel_pages() is a caller of kmap_to_page(). It only has one caller > > [shm_get_kernel_pages()] which does not need the functionality. > > > > Alter shm_get_kernel_pages() to no longer call get_kernel_pages() and remove > > get_kernel_pages(). Along the way it was noted that shm_get_kernel_pages() > > does not have any need to support vmalloc'ed addresses either. Remove that > > functionality to clean up the logic. > > > > This series also fixes is_kmap_addr() and uses it to ensure no kmap addresses > > slip in later. > > > > [1] https://lore.kernel.org/all/CAFA6WYMqEVDVW-ifoh-V9ni1zntYdes8adQKf2XXAUpqdaW53w@xxxxxxxxxxxxxx/ > > [2] https://lore.kernel.org/lkml/YzSSl1ItVlARDvG3@ZenIV > > > > To: Sumit Garg <sumit.garg@xxxxxxxxxx> > > To: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > > Cc: "Al Viro" <viro@xxxxxxxxxxxxxxxxxx> > > Cc: "Christoph Hellwig" <hch@xxxxxx> > > Cc: linux-kernel@xxxxxxxxxxxxxxx > > Cc: op-tee@xxxxxxxxxxxxxxxxxxxxxxxxx > > Cc: linux-mm@xxxxxxxxx > > Cc: Jens Wiklander <jens.wiklander@xxxxxxxxxx> > > Cc: "Fabio M. De Francesco" <fmdefrancesco@xxxxxxxxx> > > Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx> > > > > --- > > Changes in v2: > > - Al Viro: Avoid allocating the kiov. > > - Sumit: Update cover letter to clarify the motivation behind removing > > get_kernel_pages() > > - Link to v1: https://lore.kernel.org/r/20221002002326.946620-1-ira.weiny@xxxxxxxxx > > > > --- > > Ira Weiny (4): > > highmem: Enhance is_kmap_addr() to check kmap_local_page() mappings > > tee: Remove vmalloc page support > > tee: Remove call to get_kernel_pages() > > mm: Remove get_kernel_pages() > > > > drivers/tee/tee_shm.c | 37 ++++++++++--------------------------- > > include/linux/highmem-internal.h | 5 ++++- > > include/linux/mm.h | 2 -- > > mm/swap.c | 30 ------------------------------ > > 4 files changed, 14 insertions(+), 60 deletions(-) > > --- > > base-commit: 0136d86b78522bbd5755f8194c97a987f0586ba5 > > change-id: 20230203-get_kernel_pages-199342cfba79 > > > > Best regards, > > -- > > Ira Weiny <ira.weiny@xxxxxxxxx>
