linux.git/arch/powerpc/platforms/book3s, branch vsnprintf

powerpc/vas: Limit open window failure messages in log bufffer

2023-10-20T06:10:03+00:00

The VAS open window call prints error message and returns -EBUSY
after the migration suspend event initiated and until the resume
event completed on the destination system. It can cause the log
buffer filled with these error messages if the user space issues
continuous open window calls.  Similar case even for DLPAR CPU
remove event when no credits are available until the credits are
freed or with the other DLPAR CPU add event.

So changes in the patch to use pr_err_ratelimited() instead of
pr_err() to display open window failure and not-available credits
error messages.

Use pr_fmt() and make the corresponding changes to have the
consistencein prefix all pr_*() messages (vas-api.c).

Fixes: 37e6764895ef ("powerpc/pseries/vas: Add VAS migration handler")
Signed-off-by: Haren Myneni 
[mpe: Use "vas-api" as the prefix to match the file name.]
Signed-off-by: Michael Ellerman 
Link: https://msgid.link/20231019215033.1335251-1-haren@linux.ibm.com

driver core: class: remove module * from class_create()

2023-03-17T14:16:33+00:00

The module pointer in class_create() never actually did anything, and it
shouldn't have been requred to be set as a parameter even if it did
something.  So just remove it and fix up all callers of the function in
the kernel tree at the same time.

Cc: "Rafael J. Wysocki" 
Acked-by: Benjamin Tissoires 
Link: https://lore.kernel.org/r/20230313181843.1207845-4-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman

mm: replace vma->vm_flags direct modifications with modifier calls

2023-02-10T00:51:39+00:00

Replace direct modifications to vma->vm_flags with calls to modifier
functions to be able to track flag changes and to keep vma locking
correctness.

[akpm@linux-foundation.org: fix drivers/misc/open-dice.c, per Hyeonggon Yoo]
Link: https://lkml.kernel.org/r/20230126193752.297968-5-surenb@google.com
Signed-off-by: Suren Baghdasaryan 
Acked-by: Michal Hocko 
Acked-by: Mel Gorman 
Acked-by: Mike Rapoport (IBM) 
Acked-by: Sebastian Reichel 
Reviewed-by: Liam R. Howlett 
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Andy Lutomirski 
Cc: Arjun Roy 
Cc: Axel Rasmussen 
Cc: David Hildenbrand 
Cc: David Howells 
Cc: Davidlohr Bueso 
Cc: David Rientjes 
Cc: Eric Dumazet 
Cc: Greg Thelen 
Cc: Hugh Dickins 
Cc: Ingo Molnar 
Cc: Jann Horn 
Cc: Joel Fernandes 
Cc: Johannes Weiner 
Cc: Kent Overstreet 
Cc: Laurent Dufour 
Cc: Lorenzo Stoakes 
Cc: Matthew Wilcox 
Cc: Minchan Kim 
Cc: Paul E. McKenney 
Cc: Peter Oskolkov 
Cc: Peter Xu 
Cc: Peter Zijlstra 
Cc: Punit Agrawal 
Cc: Sebastian Andrzej Siewior 
Cc: Shakeel Butt 
Cc: Soheil Hassas Yeganeh 
Cc: Song Liu 
Cc: Vlastimil Babka 
Cc: Will Deacon 
Signed-off-by: Andrew Morton

mm: remove zap_page_range and create zap_vma_pages

2023-01-19T01:12:55+00:00

zap_page_range was originally designed to unmap pages within an address
range that could span multiple vmas.  While working on [1], it was
discovered that all callers of zap_page_range pass a range entirely within
a single vma.  In addition, the mmu notification call within zap_page
range does not correctly handle ranges that span multiple vmas.  When
crossing a vma boundary, a new mmu_notifier_range_init/end call pair with
the new vma should be made.

Instead of fixing zap_page_range, do the following:
- Create a new routine zap_vma_pages() that will remove all pages within
  the passed vma.  Most users of zap_page_range pass the entire vma and
  can use this new routine.
- For callers of zap_page_range not passing the entire vma, instead call
  zap_page_range_single().
- Remove zap_page_range.

[1] https://lore.kernel.org/linux-mm/20221114235507.294320-2-mike.kravetz@oracle.com/
Link: https://lkml.kernel.org/r/20230104002732.232573-1-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz 
Suggested-by: Peter Xu 
Acked-by: Michal Hocko 
Acked-by: Peter Xu 
Acked-by: Heiko Carstens 	[s390]
Reviewed-by: Christoph Hellwig 
Cc: Christian Borntraeger 
Cc: Christian Brauner 
Cc: Dave Hansen 
Cc: David Hildenbrand 
Cc: Eric Dumazet 
Cc: Matthew Wilcox 
Cc: Michael Ellerman 
Cc: Nadav Amit 
Cc: Palmer Dabbelt 
Cc: Rik van Riel 
Cc: Vlastimil Babka 
Cc: Will Deacon 
Signed-off-by: Andrew Morton

driver core: fix up some missing class.devnode() conversions.

2022-11-29T08:28:46+00:00

In commit ff62b8e6588f ("driver core: make struct class.devnode() take a
const *") the ->devnode callback changed the pointer to be const, but a
few instances of PowerPC drivers were not caught for some reason.

Fix this up by changing the pointers to be const.

Fixes: ff62b8e6588f ("driver core: make struct class.devnode() take a const *")
Cc: Michael Ellerman 
Cc: Nicholas Piggin 
Cc: Christophe Leroy 
Cc: Frederic Barrat 
Cc: Andrew Donnellan 
Cc: Arnd Bergmann 
Cc: linuxppc-dev@lists.ozlabs.org
Reported-by: Stephen Rothwell 
Link: https://lore.kernel.org/r/20221128173539.3112234-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman

powerpc/vas: fix repeated words in comments

2022-09-06T01:03:04+00:00

Delete the redundant word 'the'.

Signed-off-by: Jilin Yuan 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20220831004914.37055-1-yuanjilin@cdjrlc.com

powerpc: fix typos in comments

2022-05-05T12:12:44+00:00

Various spelling mistakes in comments.
Detected with the help of Coccinelle.

Signed-off-by: Julia Lawall 
Reviewed-by: Joel Stanley 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20220430185654.5855-1-Julia.Lawall@inria.fr

powerpc/vas: Map paste address only if window is active

2022-03-07T13:04:55+00:00

The paste address mapping is done with mmap() after the window is
opened with ioctl. The partition has to close VAS windows in the
hypervisor if it lost credits due to DLPAR core removal. But the
kernel marks these windows inactive until the previously lost
credits are available later. If the window is inactive due to
DLPAR after this mmap(), the paste instruction returns failure
until the the OS reopens this window again.

Before the user space issuing mmap(), there is a possibility of
happening DLPAR core removal event which causes the corresponding
window inactive. So if the window is not active, return mmap()
failure with -EACCES and expects the user space reissue mmap()
when the window is active or open a new window when the credit
is available.

Signed-off-by: Haren Myneni 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/bbb203c26b324534e25658cb1dbbcb5160a2f93a.camel@linux.ibm.com

powerpc/vas: Return paste instruction failure if no active window

2022-03-07T13:04:55+00:00

The VAS window may not be active if the system looses credits and
the NX generates page fault when it receives request on unmap
paste address.

The kernel handles the fault by remap new paste address if the
window is active again, Otherwise return the paste instruction
failure if the executed instruction that caused the fault was
a paste.

Signed-off-by: Nicholas Piggin 
Signed-off-by: Haren Myneni 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/492b9aefd593061d51dda67ee4d2fc449c000dce.camel@linux.ibm.com

powerpc/vas: Add paste address mmap fault handler

2022-03-07T13:04:55+00:00

The user space opens VAS windows and issues NX requests by pasting
CRB on the corresponding paste address mmap. When the system lost
credits due to core removal, the kernel has to close the window in
the hypervisor and make the window inactive by unmapping this paste
address. Also the OS has to handle NX request page faults if the user
space issue NX requests.

This handler maps the new paste address with the same VMA when the
window is active again (due to core add with DLPAR). Otherwise
returns paste failure.

Signed-off-by: Haren Myneni 
Reviewed-by: Nicholas Piggin 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/3956e1c1fdfde69127055ff1c0256c7d71104030.camel@linux.ibm.com