Commit Graph

1727 Commits

Author SHA1 Message Date
Linus Torvalds 076f14be7f The X86 entry, exception and interrupt code rework
This all started about 6 month ago with the attempt to move the Posix CPU
 timer heavy lifting out of the timer interrupt code and just have lockless
 quick checks in that code path. Trivial 5 patches.
 
 This unearthed an inconsistency in the KVM handling of task work and the
 review requested to move all of this into generic code so other
 architectures can share.
 
 Valid request and solved with another 25 patches but those unearthed
 inconsistencies vs. RCU and instrumentation.
 
 Digging into this made it obvious that there are quite some inconsistencies
 vs. instrumentation in general. The int3 text poke handling in particular
 was completely unprotected and with the batched update of trace events even
 more likely to expose to endless int3 recursion.
 
 In parallel the RCU implications of instrumenting fragile entry code came
 up in several discussions.
 
 The conclusion of the X86 maintainer team was to go all the way and make
 the protection against any form of instrumentation of fragile and dangerous
 code pathes enforcable and verifiable by tooling.
 
 A first batch of preparatory work hit mainline with commit d5f744f9a2.
 
 The (almost) full solution introduced a new code section '.noinstr.text'
 into which all code which needs to be protected from instrumentation of all
 sorts goes into. Any call into instrumentable code out of this section has
 to be annotated. objtool has support to validate this. Kprobes now excludes
 this section fully which also prevents BPF from fiddling with it and all
 'noinstr' annotated functions also keep ftrace off. The section, kprobes
 and objtool changes are already merged.
 
 The major changes coming with this are:
 
     - Preparatory cleanups
 
     - Annotating of relevant functions to move them into the noinstr.text
       section or enforcing inlining by marking them __always_inline so the
       compiler cannot misplace or instrument them.
 
     - Splitting and simplifying the idtentry macro maze so that it is now
       clearly separated into simple exception entries and the more
       interesting ones which use interrupt stacks and have the paranoid
       handling vs. CR3 and GS.
 
     - Move quite some of the low level ASM functionality into C code:
 
        - enter_from and exit to user space handling. The ASM code now calls
          into C after doing the really necessary ASM handling and the return
 	 path goes back out without bells and whistels in ASM.
 
        - exception entry/exit got the equivivalent treatment
 
        - move all IRQ tracepoints from ASM to C so they can be placed as
          appropriate which is especially important for the int3 recursion
          issue.
 
     - Consolidate the declaration and definition of entry points between 32
       and 64 bit. They share a common header and macros now.
 
     - Remove the extra device interrupt entry maze and just use the regular
       exception entry code.
 
     - All ASM entry points except NMI are now generated from the shared header
       file and the corresponding macros in the 32 and 64 bit entry ASM.
 
     - The C code entry points are consolidated as well with the help of
       DEFINE_IDTENTRY*() macros. This allows to ensure at one central point
       that all corresponding entry points share the same semantics. The
       actual function body for most entry points is in an instrumentable
       and sane state.
 
       There are special macros for the more sensitive entry points,
       e.g. INT3 and of course the nasty paranoid #NMI, #MCE, #DB and #DF.
       They allow to put the whole entry instrumentation and RCU handling
       into safe places instead of the previous pray that it is correct
       approach.
 
     - The INT3 text poke handling is now completely isolated and the
       recursion issue banned. Aside of the entry rework this required other
       isolation work, e.g. the ability to force inline bsearch.
 
     - Prevent #DB on fragile entry code, entry relevant memory and disable
       it on NMI, #MC entry, which allowed to get rid of the nested #DB IST
       stack shifting hackery.
 
     - A few other cleanups and enhancements which have been made possible
       through this and already merged changes, e.g. consolidating and
       further restricting the IDT code so the IDT table becomes RO after
       init which removes yet another popular attack vector
 
     - About 680 lines of ASM maze are gone.
 
 There are a few open issues:
 
    - An escape out of the noinstr section in the MCE handler which needs
      some more thought but under the aspect that MCE is a complete
      trainwreck by design and the propability to survive it is low, this was
      not high on the priority list.
 
    - Paravirtualization
 
      When PV is enabled then objtool complains about a bunch of indirect
      calls out of the noinstr section. There are a few straight forward
      ways to fix this, but the other issues vs. general correctness were
      more pressing than parawitz.
 
    - KVM
 
      KVM is inconsistent as well. Patches have been posted, but they have
      not yet been commented on or picked up by the KVM folks.
 
    - IDLE
 
      Pretty much the same problems can be found in the low level idle code
      especially the parts where RCU stopped watching. This was beyond the
      scope of the more obvious and exposable problems and is on the todo
      list.
 
 The lesson learned from this brain melting exercise to morph the evolved
 code base into something which can be validated and understood is that once
 again the violation of the most important engineering principle
 "correctness first" has caused quite a few people to spend valuable time on
 problems which could have been avoided in the first place. The "features
 first" tinkering mindset really has to stop.
 
 With that I want to say thanks to everyone involved in contributing to this
 effort. Special thanks go to the following people (alphabetical order):
 
    Alexandre Chartre
    Andy Lutomirski
    Borislav Petkov
    Brian Gerst
    Frederic Weisbecker
    Josh Poimboeuf
    Juergen Gross
    Lai Jiangshan
    Macro Elver
    Paolo Bonzini
    Paul McKenney
    Peter Zijlstra
    Vitaly Kuznetsov
    Will Deacon
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Merge tag 'x86-entry-2020-06-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 entry updates from Thomas Gleixner:
 "The x86 entry, exception and interrupt code rework

  This all started about 6 month ago with the attempt to move the Posix
  CPU timer heavy lifting out of the timer interrupt code and just have
  lockless quick checks in that code path. Trivial 5 patches.

  This unearthed an inconsistency in the KVM handling of task work and
  the review requested to move all of this into generic code so other
  architectures can share.

  Valid request and solved with another 25 patches but those unearthed
  inconsistencies vs. RCU and instrumentation.

  Digging into this made it obvious that there are quite some
  inconsistencies vs. instrumentation in general. The int3 text poke
  handling in particular was completely unprotected and with the batched
  update of trace events even more likely to expose to endless int3
  recursion.

  In parallel the RCU implications of instrumenting fragile entry code
  came up in several discussions.

  The conclusion of the x86 maintainer team was to go all the way and
  make the protection against any form of instrumentation of fragile and
  dangerous code pathes enforcable and verifiable by tooling.

  A first batch of preparatory work hit mainline with commit
  d5f744f9a2 ("Pull x86 entry code updates from Thomas Gleixner")

  That (almost) full solution introduced a new code section
  '.noinstr.text' into which all code which needs to be protected from
  instrumentation of all sorts goes into. Any call into instrumentable
  code out of this section has to be annotated. objtool has support to
  validate this.

  Kprobes now excludes this section fully which also prevents BPF from
  fiddling with it and all 'noinstr' annotated functions also keep
  ftrace off. The section, kprobes and objtool changes are already
  merged.

  The major changes coming with this are:

    - Preparatory cleanups

    - Annotating of relevant functions to move them into the
      noinstr.text section or enforcing inlining by marking them
      __always_inline so the compiler cannot misplace or instrument
      them.

    - Splitting and simplifying the idtentry macro maze so that it is
      now clearly separated into simple exception entries and the more
      interesting ones which use interrupt stacks and have the paranoid
      handling vs. CR3 and GS.

    - Move quite some of the low level ASM functionality into C code:

       - enter_from and exit to user space handling. The ASM code now
         calls into C after doing the really necessary ASM handling and
         the return path goes back out without bells and whistels in
         ASM.

       - exception entry/exit got the equivivalent treatment

       - move all IRQ tracepoints from ASM to C so they can be placed as
         appropriate which is especially important for the int3
         recursion issue.

    - Consolidate the declaration and definition of entry points between
      32 and 64 bit. They share a common header and macros now.

    - Remove the extra device interrupt entry maze and just use the
      regular exception entry code.

    - All ASM entry points except NMI are now generated from the shared
      header file and the corresponding macros in the 32 and 64 bit
      entry ASM.

    - The C code entry points are consolidated as well with the help of
      DEFINE_IDTENTRY*() macros. This allows to ensure at one central
      point that all corresponding entry points share the same
      semantics. The actual function body for most entry points is in an
      instrumentable and sane state.

      There are special macros for the more sensitive entry points, e.g.
      INT3 and of course the nasty paranoid #NMI, #MCE, #DB and #DF.
      They allow to put the whole entry instrumentation and RCU handling
      into safe places instead of the previous pray that it is correct
      approach.

    - The INT3 text poke handling is now completely isolated and the
      recursion issue banned. Aside of the entry rework this required
      other isolation work, e.g. the ability to force inline bsearch.

    - Prevent #DB on fragile entry code, entry relevant memory and
      disable it on NMI, #MC entry, which allowed to get rid of the
      nested #DB IST stack shifting hackery.

    - A few other cleanups and enhancements which have been made
      possible through this and already merged changes, e.g.
      consolidating and further restricting the IDT code so the IDT
      table becomes RO after init which removes yet another popular
      attack vector

    - About 680 lines of ASM maze are gone.

  There are a few open issues:

   - An escape out of the noinstr section in the MCE handler which needs
     some more thought but under the aspect that MCE is a complete
     trainwreck by design and the propability to survive it is low, this
     was not high on the priority list.

   - Paravirtualization

     When PV is enabled then objtool complains about a bunch of indirect
     calls out of the noinstr section. There are a few straight forward
     ways to fix this, but the other issues vs. general correctness were
     more pressing than parawitz.

   - KVM

     KVM is inconsistent as well. Patches have been posted, but they
     have not yet been commented on or picked up by the KVM folks.

   - IDLE

     Pretty much the same problems can be found in the low level idle
     code especially the parts where RCU stopped watching. This was
     beyond the scope of the more obvious and exposable problems and is
     on the todo list.

  The lesson learned from this brain melting exercise to morph the
  evolved code base into something which can be validated and understood
  is that once again the violation of the most important engineering
  principle "correctness first" has caused quite a few people to spend
  valuable time on problems which could have been avoided in the first
  place. The "features first" tinkering mindset really has to stop.

  With that I want to say thanks to everyone involved in contributing to
  this effort. Special thanks go to the following people (alphabetical
  order): Alexandre Chartre, Andy Lutomirski, Borislav Petkov, Brian
  Gerst, Frederic Weisbecker, Josh Poimboeuf, Juergen Gross, Lai
  Jiangshan, Macro Elver, Paolo Bonzin,i Paul McKenney, Peter Zijlstra,
  Vitaly Kuznetsov, and Will Deacon"

* tag 'x86-entry-2020-06-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (142 commits)
  x86/entry: Force rcu_irq_enter() when in idle task
  x86/entry: Make NMI use IDTENTRY_RAW
  x86/entry: Treat BUG/WARN as NMI-like entries
  x86/entry: Unbreak __irqentry_text_start/end magic
  x86/entry: __always_inline CR2 for noinstr
  lockdep: __always_inline more for noinstr
  x86/entry: Re-order #DB handler to avoid *SAN instrumentation
  x86/entry: __always_inline arch_atomic_* for noinstr
  x86/entry: __always_inline irqflags for noinstr
  x86/entry: __always_inline debugreg for noinstr
  x86/idt: Consolidate idt functionality
  x86/idt: Cleanup trap_init()
  x86/idt: Use proper constants for table size
  x86/idt: Add comments about early #PF handling
  x86/idt: Mark init only functions __init
  x86/entry: Rename trace_hardirqs_off_prepare()
  x86/entry: Clarify irq_{enter,exit}_rcu()
  x86/entry: Remove DBn stacks
  x86/entry: Remove debug IDT frobbing
  x86/entry: Optimize local_db_save() for virt
  ...
2020-06-13 10:05:47 -07:00
Linus Torvalds d2d5439df2 xen: branch for v5.8-rc1
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Merge tag 'for-linus-5.8b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen updates from Juergen Gross:

 - several smaller cleanups

 - a fix for a Xen guest regression with CPU offlining

 - a small fix in the xen pvcalls backend driver

 - an update of MAINTAINERS

* tag 'for-linus-5.8b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  MAINTAINERS: Update PARAVIRT_OPS_INTERFACE and VMWARE_HYPERVISOR_INTERFACE
  xen/pci: Get rid of verbose_request and use dev_dbg() instead
  xenbus: Use dev_printk() when possible
  xen-pciback: Use dev_printk() when possible
  xen: enable BALLOON_MEMORY_HOTPLUG by default
  xen: expand BALLOON_MEMORY_HOTPLUG description
  xen/pvcalls: Make pvcalls_back_global static
  xen/cpuhotplug: Fix initial CPU offlining for PV(H) guests
  xen-platform: Constify dev_pm_ops
  xen/pvcalls-back: test for errors when calling backend_connect()
2020-06-12 11:00:45 -07:00
Thomas Gleixner cb09ea2924 x86/entry: Convert XEN hypercall vector to IDTENTRY_SYSVEC
Convert the last oldstyle defined vector to IDTENTRY_SYSVEC:

  - Implement the C entry point with DEFINE_IDTENTRY_SYSVEC
  - Emit the ASM stub with DECLARE_IDTENTRY_SYSVEC
  - Remove the ASM idtentries in 64-bit
  - Remove the BUILD_INTERRUPT entries in 32-bit
  - Remove the old prototypes

Fixup the related XEN code by providing the primary C entry point in x86 to
avoid cluttering the generic code with X86'isms.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lore.kernel.org/r/20200521202119.741950104@linutronix.de
2020-06-11 15:15:15 +02:00
Thomas Gleixner 2f6474e463 x86/entry: Switch XEN/PV hypercall entry to IDTENTRY
Convert the XEN/PV hypercall to IDTENTRY:

  - Emit the ASM stub with DECLARE_IDTENTRY
  - Remove the ASM idtentry in 64-bit
  - Remove the open coded ASM entry code in 32-bit
  - Remove the old prototypes

The handler stubs need to stay in ASM code as they need corner case handling
and adjustment of the stack pointer.

Provide a new C function which invokes the entry/exit handling and calls
into the XEN handler on the interrupt stack if required.

The exit code is slightly different from the regular idtentry_exit() on
non-preemptible kernels. If the hypercall is preemptible and need_resched()
is set then XEN provides a preempt hypercall scheduling function.

Move this functionality into the entry code so it can use the existing
idtentry functionality.

[ mingo: Build fixes. ]

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Juergen Gross <jgross@suse.com>
Tested-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20200521202118.055270078@linutronix.de
2020-06-11 15:15:08 +02:00
Vitaly Kuznetsov a0bb51f263 x86/xen: Split HVM vector callback setup and interrupt gate allocation
As a preparatory change for making alloc_intr_gate() __init split
xen_callback_vector() into callback vector setup via hypercall
(xen_setup_callback_vector()) and interrupt gate allocation
(xen_alloc_callback_vector()).

xen_setup_callback_vector() is being called twice: on init and upon
system resume from xen_hvm_post_suspend(). alloc_intr_gate() only
needs to be called once.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200428093824.1451532-2-vkuznets@redhat.com
2020-06-11 15:14:32 +02:00
Linus Torvalds 4152d146ee Merge branch 'rwonce/rework' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux
Pull READ/WRITE_ONCE rework from Will Deacon:
 "This the READ_ONCE rework I've been working on for a while, which
  bumps the minimum GCC version and improves code-gen on arm64 when
  stack protector is enabled"

[ Side note: I'm _really_ tempted to raise the minimum gcc version to
  4.9, so that we can just say that we require _Generic() support.

  That would allow us to more cleanly handle a lot of the cases where we
  depend on very complex macros with 'sizeof' or __builtin_choose_expr()
  with __builtin_types_compatible_p() etc.

  This branch has a workaround for sparse not handling _Generic(),
  either, but that was already fixed in the sparse development branch,
  so it's really just gcc-4.9 that we'd require.   - Linus ]

* 'rwonce/rework' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux:
  compiler_types.h: Use unoptimized __unqual_scalar_typeof for sparse
  compiler_types.h: Optimize __unqual_scalar_typeof compilation time
  compiler.h: Enforce that READ_ONCE_NOCHECK() access size is sizeof(long)
  compiler-types.h: Include naked type in __pick_integer_type() match
  READ_ONCE: Fix comment describing 2x32-bit atomicity
  gcov: Remove old GCC 3.4 support
  arm64: barrier: Use '__unqual_scalar_typeof' for acquire/release macros
  locking/barriers: Use '__unqual_scalar_typeof' for load-acquire macros
  READ_ONCE: Drop pointer qualifiers when reading from scalar types
  READ_ONCE: Enforce atomicity for {READ,WRITE}_ONCE() memory accesses
  READ_ONCE: Simplify implementations of {READ,WRITE}_ONCE()
  arm64: csum: Disable KASAN for do_csum()
  fault_inject: Don't rely on "return value" from WRITE_ONCE()
  net: tls: Avoid assigning 'const' pointer to non-const pointer
  netfilter: Avoid assigning 'const' pointer to non-const pointer
  compiler/gcc: Raise minimum GCC version for kernel builds to 4.8
2020-06-10 14:46:54 -07:00
Michel Lespinasse c1e8d7c6a7 mmap locking API: convert mmap_sem comments
Convert comments that reference mmap_sem to reference mmap_lock instead.

[akpm@linux-foundation.org: fix up linux-next leftovers]
[akpm@linux-foundation.org: s/lockaphore/lock/, per Vlastimil]
[akpm@linux-foundation.org: more linux-next fixups, per Michel]

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Laurent Dufour <ldufour@linux.ibm.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-13-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:14 -07:00
Michel Lespinasse d8ed45c5dc mmap locking API: use coccinelle to convert mmap_sem rwsem call sites
This change converts the existing mmap_sem rwsem calls to use the new mmap
locking API instead.

The change is generated using coccinelle with the following rule:

// spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir .

@@
expression mm;
@@
(
-init_rwsem
+mmap_init_lock
|
-down_write
+mmap_write_lock
|
-down_write_killable
+mmap_write_lock_killable
|
-down_write_trylock
+mmap_write_trylock
|
-up_write
+mmap_write_unlock
|
-downgrade_write
+mmap_write_downgrade
|
-down_read
+mmap_read_lock
|
-down_read_killable
+mmap_read_lock_killable
|
-down_read_trylock
+mmap_read_trylock
|
-up_read
+mmap_read_unlock
)
-(&mm->mmap_sem)
+(mm)

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:14 -07:00
Mike Rapoport e31cf2f4ca mm: don't include asm/pgtable.h if linux/mm.h is already included
Patch series "mm: consolidate definitions of page table accessors", v2.

The low level page table accessors (pXY_index(), pXY_offset()) are
duplicated across all architectures and sometimes more than once.  For
instance, we have 31 definition of pgd_offset() for 25 supported
architectures.

Most of these definitions are actually identical and typically it boils
down to, e.g.

static inline unsigned long pmd_index(unsigned long address)
{
        return (address >> PMD_SHIFT) & (PTRS_PER_PMD - 1);
}

static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address)
{
        return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(address);
}

These definitions can be shared among 90% of the arches provided
XYZ_SHIFT, PTRS_PER_XYZ and xyz_page_vaddr() are defined.

For architectures that really need a custom version there is always
possibility to override the generic version with the usual ifdefs magic.

These patches introduce include/linux/pgtable.h that replaces
include/asm-generic/pgtable.h and add the definitions of the page table
accessors to the new header.

This patch (of 12):

The linux/mm.h header includes <asm/pgtable.h> to allow inlining of the
functions involving page table manipulations, e.g.  pte_alloc() and
pmd_alloc().  So, there is no point to explicitly include <asm/pgtable.h>
in the files that include <linux/mm.h>.

The include statements in such cases are remove with a simple loop:

	for f in $(git grep -l "include <linux/mm.h>") ; do
		sed -i -e '/include <asm\/pgtable.h>/ d' $f
	done

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-1-rppt@kernel.org
Link: http://lkml.kernel.org/r/20200514170327.31389-2-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Boris Ostrovsky 4969a3a2cd xen/pci: Get rid of verbose_request and use dev_dbg() instead
Information printed under verbose_request is clearly used for debugging
only. Remove it and use dev_dbg() instead.

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/1590719092-8578-1-git-send-email-boris.ostrovsky@oracle.com
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-05-29 10:44:59 -05:00
Bjorn Helgaas 64b3eaf371 xenbus: Use dev_printk() when possible
Use dev_printk() when possible to include device and driver information in
the conventional format.

Add "#define dev_fmt" to preserve KBUILD_MODNAME in messages.

No functional change intended.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20200527174326.254329-3-helgaas@kernel.org
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-05-27 17:28:07 -05:00
Bjorn Helgaas 6904945420 xen-pciback: Use dev_printk() when possible
Use dev_printk() when possible to include device and driver information in
the conventional format.

Add "#define dev_fmt" when needed to preserve DRV_NAME or KBUILD_MODNAME in
messages.

No functional change intended.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20200527174326.254329-2-helgaas@kernel.org
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-05-27 17:27:37 -05:00
Roger Pau Monne 2abb65a39b xen: enable BALLOON_MEMORY_HOTPLUG by default
Without it a PVH dom0 is mostly useless, as it would balloon down huge
amounts of RAM in order get physical address space to map foreign
memory and grants, ultimately leading to an out of memory situation.

Such option is also needed for HVM or PVH driver domains, since they
also require mapping grants into physical memory regions.

Suggested-by: Ian Jackson <ian.jackson@eu.citrix.com>
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Link: https://lore.kernel.org/r/20200324150015.50496-2-roger.pau@citrix.com
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-05-21 18:11:03 -05:00
Roger Pau Monne 0df683ff74 xen: expand BALLOON_MEMORY_HOTPLUG description
To mention it's also useful for PVH or HVM domains that require
mapping foreign memory or grants.

[boris: "non PV" instead of "translated" at Juergen's request]

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Link: https://lore.kernel.org/r/20200324150015.50496-1-roger.pau@citrix.com
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-05-21 18:10:51 -05:00
YueHaibing 5333875301 xen/pvcalls: Make pvcalls_back_global static
Fix sparse warning:

drivers/xen/pvcalls-back.c:30:3: warning:
 symbol 'pvcalls_back_global' was not declared. Should it be static?

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20200410115620.33024-1-yuehaibing@huawei.com
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-05-21 13:06:42 -05:00
Boris Ostrovsky c54b071c19 xen/cpuhotplug: Fix initial CPU offlining for PV(H) guests
Commit a926f81d2f ("xen/cpuhotplug: Replace cpu_up/down() with
device_online/offline()") replaced cpu_down() with device_offline()
call which requires that the CPU has been registered before. This
registration, however, happens later from topology_init() which
is called as subsys_initcall(). setup_vcpu_hotplug_event(), on the
other hand, is invoked earlier, during arch_initcall().

As result, booting a PV(H) guest with vcpus < maxvcpus causes a crash.

Move setup_vcpu_hotplug_event() (and therefore setup_cpu_watcher()) to
late_initcall(). In addition, instead of performing all offlining steps
in setup_cpu_watcher() simply call disable_hotplug_cpu().

Fixes: a926f81d2f (xen/cpuhotplug: Replace cpu_up/down() with device_online/offline()"
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/1588976923-3667-1-git-send-email-boris.ostrovsky@oracle.com
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-05-21 13:01:45 -05:00
Rikard Falkeborn c17db64044 xen-platform: Constify dev_pm_ops
dev_pm_ops is never modified, so mark it const to allow the compiler to
put it in read-only memory.

Before:
   text    data     bss     dec     hex filename
   2457    1668     256    4381    111d drivers/xen/platform-pci.o

After:
   text    data     bss     dec     hex filename
   2681    1444     256    4381    111d drivers/xen/platform-pci.o

Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Link: https://lore.kernel.org/r/20200509134755.15038-1-rikard.falkeborn@gmail.com
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-05-21 13:00:39 -05:00
Juergen Gross c8d70a29d6 xen/pvcalls-back: test for errors when calling backend_connect()
backend_connect() can fail, so switch the device to connected only if
no error occurred.

Fixes: 0a9c75c2c7 ("xen/pvcalls: xenbus state handling")
Cc: stable@vger.kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20200511074231.19794-1-jgross@suse.com
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-05-21 12:59:15 -05:00
Thomas Gleixner 8a29204f3e xen/privcmd: Remove unneeded asm/tlb.h include
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200421092600.236617960@linutronix.de
2020-04-26 18:51:19 +02:00
Linus Torvalds d0a4ebe7d1 xen: branch for v5.7-rc2
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Merge tag 'for-linus-5.7-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen update from Juergen Gross:

 - a small cleanup patch

 - a security fix for a bug in the Xen hypervisor to avoid enabling Xen
   guests to crash dom0 on an unfixed hypervisor.

* tag 'for-linus-5.7-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  arm/xen: make _xen_start_info static
  xen/xenbus: ensure xenbus_map_ring_valloc() returns proper grant status
2020-04-17 10:35:17 -07:00
Will Deacon 9e343b467c READ_ONCE: Enforce atomicity for {READ,WRITE}_ONCE() memory accesses
{READ,WRITE}_ONCE() cannot guarantee atomicity for arbitrary data sizes.
This can be surprising to callers that might incorrectly be expecting
atomicity for accesses to aggregate structures, although there are other
callers where tearing is actually permissable (e.g. if they are using
something akin to sequence locking to protect the access).

Linus sayeth:

  | We could also look at being stricter for the normal READ/WRITE_ONCE(),
  | and require that they are
  |
  | (a) regular integer types
  |
  | (b) fit in an atomic word
  |
  | We actually did (b) for a while, until we noticed that we do it on
  | loff_t's etc and relaxed the rules. But maybe we could have a
  | "non-atomic" version of READ/WRITE_ONCE() that is used for the
  | questionable cases?

The slight snag is that we also have to support 64-bit accesses on 32-bit
architectures, as these appear to be widespread and tend to work out ok
if either the architecture supports atomic 64-bit accesses (x86, armv7)
or if the variable being accesses represents a virtual address and
therefore only requires 32-bit atomicity in practice.

Take a step in that direction by introducing a variant of
'compiletime_assert_atomic_type()' and use it to check the pointer
argument to {READ,WRITE}_ONCE(). Expose __{READ,WRITE}_ONCE() variants
which are allowed to tear and convert the one broken caller over to the
new macros.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Will Deacon <will@kernel.org>
2020-04-16 12:28:07 +01:00
Juergen Gross 6b51fd3f65 xen/xenbus: ensure xenbus_map_ring_valloc() returns proper grant status
xenbus_map_ring_valloc() maps a ring page and returns the status of the
used grant (0 meaning success).

There are Xen hypervisors which might return the value 1 for the status
of a failed grant mapping due to a bug. Some callers of
xenbus_map_ring_valloc() test for errors by testing the returned status
to be less than zero, resulting in no error detected and crashing later
due to a not available ring page.

Set the return value of xenbus_map_ring_valloc() to GNTST_general_error
in case the grant status reported by Xen is greater than zero.

This is part of XSA-316.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Wei Liu <wl@xen.org>
Link: https://lore.kernel.org/r/20200326080358.1018-1-jgross@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
2020-04-14 15:09:37 +02:00
Linus Torvalds e6383b185a xen: branch for v5.7-rc1b
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Merge tag 'for-linus-5.7-rc1b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull more xen updates from Juergen Gross:

 - two cleanups

 - fix a boot regression introduced in this merge window

 - fix wrong use of memory allocation flags

* tag 'for-linus-5.7-rc1b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  x86/xen: fix booting 32-bit pv guest
  x86/xen: make xen_pvmmu_arch_setup() static
  xen/blkfront: fix memory allocation flags in blkfront_setup_indirect()
  xen: Use evtchn_type_t as a type for event channels
2020-04-10 17:20:06 -07:00
Yan Yankovskyi 0102e4efda xen: Use evtchn_type_t as a type for event channels
Make event channel functions pass event channel port using
evtchn_port_t type. It eliminates signed <-> unsigned conversion.

Signed-off-by: Yan Yankovskyi <yyankovskyi@gmail.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/20200323152343.GA28422@kbp1-lhp-F74019
Signed-off-by: Juergen Gross <jgross@suse.com>
2020-04-07 12:12:54 +02:00
Linus Torvalds 6cd3d4019b xen: branch for v5.7-rc1
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Merge tag 'for-linus-5.7-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen updates from Juergen Gross:

 - a cleanup patch removing an unused function

 - a small fix for the xen pciback driver

 - a series for making the unwinder hyppay with the Xen PV guest idle
   task stacks

* tag 'for-linus-5.7-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  x86/xen: Make the secondary CPU idle tasks reliable
  x86/xen: Make the boot CPU idle task reliable
  xen-pciback: fix INTERRUPT_TYPE_* defines
  xen/xenbus: remove unused xenbus_map_ring()
2020-04-03 12:51:46 -07:00
Linus Torvalds 992a1a3b45 CPU (hotplug) updates:
- Support for locked CSD objects in smp_call_function_single_async()
     which allows to simplify callsites in the scheduler core and MIPS
 
   - Treewide consolidation of CPU hotplug functions which ensures the
     consistency between the sysfs interface and kernel state. The low level
     functions cpu_up/down() are now confined to the core code and not
     longer accessible from random code.
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Merge tag 'smp-core-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull core SMP updates from Thomas Gleixner:
 "CPU (hotplug) updates:

   - Support for locked CSD objects in smp_call_function_single_async()
     which allows to simplify callsites in the scheduler core and MIPS

   - Treewide consolidation of CPU hotplug functions which ensures the
     consistency between the sysfs interface and kernel state. The low
     level functions cpu_up/down() are now confined to the core code and
     not longer accessible from random code"

* tag 'smp-core-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits)
  cpu/hotplug: Ignore pm_wakeup_pending() for disable_nonboot_cpus()
  cpu/hotplug: Hide cpu_up/down()
  cpu/hotplug: Move bringup of secondary CPUs out of smp_init()
  torture: Replace cpu_up/down() with add/remove_cpu()
  firmware: psci: Replace cpu_up/down() with add/remove_cpu()
  xen/cpuhotplug: Replace cpu_up/down() with device_online/offline()
  parisc: Replace cpu_up/down() with add/remove_cpu()
  sparc: Replace cpu_up/down() with add/remove_cpu()
  powerpc: Replace cpu_up/down() with add/remove_cpu()
  x86/smp: Replace cpu_up/down() with add/remove_cpu()
  arm64: hibernate: Use bringup_hibernate_cpu()
  cpu/hotplug: Provide bringup_hibernate_cpu()
  arm64: Use reboot_cpu instead of hardconding it to 0
  arm64: Don't use disable_nonboot_cpus()
  ARM: Use reboot_cpu instead of hardcoding it to 0
  ARM: Don't use disable_nonboot_cpus()
  ia64: Replace cpu_down() with smp_shutdown_nonboot_cpus()
  cpu/hotplug: Create a new function to shutdown nonboot cpus
  cpu/hotplug: Add new {add,remove}_cpu() functions
  sched/core: Remove rq.hrtick_csd_pending
  ...
2020-03-30 18:06:39 -07:00
Marek Marczykowski-Górecki 69086bd698 xen-pciback: fix INTERRUPT_TYPE_* defines
xen_pcibk_get_interrupt_type() assumes INTERRUPT_TYPE_NONE being 0
(initialize ret to 0 and return as INTERRUPT_TYPE_NONE).
Fix the definition to make INTERRUPT_TYPE_NONE really 0, and also shift
other values to not leave holes.
But also, do not assume INTERRUPT_TYPE_NONE being 0 anymore to avoid
similar confusions in the future.

Fixes: 476878e4b2 ("xen-pciback: optionally allow interrupt enable flag writes")
Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2020-03-30 17:31:57 +02:00
Juergen Gross b28089a7ad xen/xenbus: remove unused xenbus_map_ring()
xenbus_map_ring() is used nowhere in the tree, remove it.
xenbus_unmap_ring() is used only locally, so make it static and move it
up.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2020-03-30 17:30:46 +02:00
Qais Yousef a926f81d2f xen/cpuhotplug: Replace cpu_up/down() with device_online/offline()
The core device API performs extra housekeeping bits that are missing
from directly calling cpu_up/down().

See commit a6717c01dd ("powerpc/rtas: use device model APIs and
serialization during LPM") for an example description of what might go
wrong.

This also prepares to make cpu_up/down() a private interface of the cpu
subsystem.

Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lkml.kernel.org/r/20200323135110.30522-14-qais.yousef@arm.com
2020-03-25 12:59:36 +01:00
Juergen Gross 2f69a110e7 xen/xenbus: fix locking
Commit 060eabe8fb ("xenbus/backend: Protect xenbus callback with
lock") introduced a bug by holding a lock while calling a function
which might schedule.

Fix that by using a semaphore instead.

Fixes: 060eabe8fb ("xenbus/backend: Protect xenbus callback with lock")
Signed-off-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20200305100323.16736-1-jgross@suse.com
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-03-05 09:42:23 -06:00
Dongli Zhang 8130b9d5b5 xenbus: req->err should be updated before req->state
This patch adds the barrier to guarantee that req->err is always updated
before req->state.

Otherwise, read_reply() would not return ERR_PTR(req->err) but
req->body, when process_writes()->xb_write() is failed.

Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>
Link: https://lore.kernel.org/r/20200303221423.21962-2-dongli.zhang@oracle.com
Reviewed-by: Julien Grall <jgrall@amazon.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-03-05 09:42:01 -06:00
Dongli Zhang 1b6a51e86c xenbus: req->body should be updated before req->state
The req->body should be updated before req->state is updated and the
order should be guaranteed by a barrier.

Otherwise, read_reply() might return req->body = NULL.

Below is sample callstack when the issue is reproduced on purpose by
reordering the updates of req->body and req->state and adding delay in
code between updates of req->state and req->body.

[   22.356105] general protection fault: 0000 [#1] SMP PTI
[   22.361185] CPU: 2 PID: 52 Comm: xenwatch Not tainted 5.5.0xen+ #6
[   22.366727] Hardware name: Xen HVM domU, BIOS ...
[   22.372245] RIP: 0010:_parse_integer_fixup_radix+0x6/0x60
... ...
[   22.392163] RSP: 0018:ffffb2d64023fdf0 EFLAGS: 00010246
[   22.395933] RAX: 0000000000000000 RBX: 75746e7562755f6d RCX: 0000000000000000
[   22.400871] RDX: 0000000000000000 RSI: ffffb2d64023fdfc RDI: 75746e7562755f6d
[   22.405874] RBP: 0000000000000000 R08: 00000000000001e8 R09: 0000000000cdcdcd
[   22.410945] R10: ffffb2d6402ffe00 R11: ffff9d95395eaeb0 R12: ffff9d9535935000
[   22.417613] R13: ffff9d9526d4a000 R14: ffff9d9526f4f340 R15: ffff9d9537654000
[   22.423726] FS:  0000000000000000(0000) GS:ffff9d953bc80000(0000) knlGS:0000000000000000
[   22.429898] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   22.434342] CR2: 000000c4206a9000 CR3: 00000001ea3fc002 CR4: 00000000001606e0
[   22.439645] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   22.444941] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   22.450342] Call Trace:
[   22.452509]  simple_strtoull+0x27/0x70
[   22.455572]  xenbus_transaction_start+0x31/0x50
[   22.459104]  netback_changed+0x76c/0xcc1 [xen_netfront]
[   22.463279]  ? find_watch+0x40/0x40
[   22.466156]  xenwatch_thread+0xb4/0x150
[   22.469309]  ? wait_woken+0x80/0x80
[   22.472198]  kthread+0x10e/0x130
[   22.474925]  ? kthread_park+0x80/0x80
[   22.477946]  ret_from_fork+0x35/0x40
[   22.480968] Modules linked in: xen_kbdfront xen_fbfront(+) xen_netfront xen_blkfront
[   22.486783] ---[ end trace a9222030a747c3f7 ]---
[   22.490424] RIP: 0010:_parse_integer_fixup_radix+0x6/0x60

The virt_rmb() is added in the 'true' path of test_reply(). The "while"
is changed to "do while" so that test_reply() is used as a read memory
barrier.

Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>
Link: https://lore.kernel.org/r/20200303221423.21962-1-dongli.zhang@oracle.com
Reviewed-by: Julien Grall <jgrall@amazon.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-03-05 09:41:59 -06:00
Gustavo A. R. Silva e8dc73c9f9 xen: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Link: https://lore.kernel.org/r/20200226212612.GA4663@embeddedor
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-03-05 09:41:58 -06:00
Linus Torvalds 54dedb5b57 xen: branch for v5.6-rc3
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Merge tag 'for-linus-5.6-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen fixes from Juergen Gross:
 "Two small fixes for Xen:

   - a fix to avoid warnings with new gcc

   - a fix for incorrectly disabled interrupts when calling
     _cond_resched()"

* tag 'for-linus-5.6-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen: Enable interrupts when calling _cond_resched()
  x86/xen: Distribute switch variables for initialization
2020-02-21 16:10:10 -08:00
Thomas Gleixner 8645e56a4a xen: Enable interrupts when calling _cond_resched()
xen_maybe_preempt_hcall() is called from the exception entry point
xen_do_hypervisor_callback with interrupts disabled.

_cond_resched() evades the might_sleep() check in cond_resched() which
would have caught that and schedule_debug() unfortunately lacks a check
for irqs_disabled().

Enable interrupts around the call and use cond_resched() to catch future
issues.

Fixes: fdfd811ddd ("x86/xen: allow privcmd hypercalls to be preempted")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/878skypjrh.fsf@nanos.tec.linutronix.de
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-02-20 16:40:38 -06:00
Linus Torvalds d271ab2923 xen: branch for v5.6-rc1
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Merge tag 'for-linus-5.6-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen updates from Juergen Gross:

 - fix a bug introduced in 5.5 in the Xen gntdev driver

 - fix the Xen balloon driver when running on ancient Xen versions

 - allow Xen stubdoms to control interrupt enable flags of
   passed-through PCI cards

 - release resources in Xen backends under memory pressure

* tag 'for-linus-5.6-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/blkback: Consistently insert one empty line between functions
  xen/blkback: Remove unnecessary static variable name prefixes
  xen/blkback: Squeeze page pools if a memory pressure is detected
  xenbus/backend: Protect xenbus callback with lock
  xenbus/backend: Add memory pressure handler callback
  xen/gntdev: Do not use mm notifiers with autotranslating guests
  xen/balloon: Support xend-based toolstack take two
  xen-pciback: optionally allow interrupt enable flag writes
2020-02-05 17:44:14 +00:00
Linus Torvalds 9f68e3655a drm pull for 5.6-rc1
uapi:
 - dma-buf heaps added (and fixed)
 - command line add support for panel oreientation
 - command line allow overriding penguin count
 
 drm:
 - mipi dsi definition updates
 - lockdep annotations for dma_resv
 - remove dma-buf kmap/kunmap support
 - constify fb_ops in all fbdev drivers
 - MST fix for daisy chained hotplug-
 - CTA-861-G modes with VIC >= 193 added
 - fix drm_panel_of_backlight export
 - LVDS decoder support
 - more device based logging support
 - scanline alighment for dumb buffers
 - MST DSC helpers
 
 scheduler:
 - documentation fixes
 - job distribution improvements
 
 panel:
 - Logic PD type 28 panel support
 - Jimax8729d MIPI-DSI
 - igenic JZ4770
 - generic DSI devicetree bindings
 - sony acx424AKP panel
 - Leadtek LTK500HD1829
 - xinpeng XPP055C272
 - AUO B116XAK01
 - GiantPlus GPM940B0
 - BOE NV140FHM-N49
 - Satoz SAT050AT40H12R2
 - Sharp LS020B1DD01D panels.
 
 ttm:
 - use blocking WW lock
 
 i915:
 - hw/uapi state separation
 - Lock annotation improvements
 - selftest improvements
 - ICL/TGL DSI VDSC support
 - VBT parsing improvments
 - Display refactoring
 - DSI updates + fixes
 - HDCP 2.2 for CFL
 - CML PCI ID fixes
 - GLK+ fbc fix
 - PSR fixes
 - GEN/GT refactor improvments
 - DP MST fixes
 - switch context id alloc to xarray
 - workaround updates
 - LMEM debugfs support
 - tiled monitor fixes
 - ICL+ clock gating programming removed
 - DP MST disable sequence fixed
 - LMEM discontiguous object maps
 - prefaulting for discontiguous objects
 - use LMEM for dumb buffers if possible
 - add LMEM mmap support
 
 amdgpu:
 - enable sync object timelines for vulkan
 - MST atomic routines
 - enable MST DSC support
 - add DMCUB display microengine support
 - DC OEM i2c support
 - Renoir DC fixes
 - Initial HDCP 2.x support
 - BACO support for Arcturus
 - Use BACO for runtime PM power save
 - gfxoff on navi10
 - gfx10 golden updates and fixes
 - DCN support on POWER
 - GFXOFF for raven1 refresh
 - MM engine idle handlers cleanup
 - 10bpc EDP panel fixes
 - renoir watermark fixes
 - SR-IOV fixes
 - Arcturus VCN fixes
 - GDDR6 training fixes
 - freesync fixes
 - Pollock support
 
 amdkfd:
 - unify more codepath with amdgpu
 - use KIQ to setup HIQ rather than MMIO
 
 radeon:
 - fix vma fault handler race
 - PPC DMA fix
 - register check fixes for r100/r200
 
 nouveau:
 - mmap_sem vs dma_resv fix
 - rewrite the ACR secure boot code for Turing
 - TU10x graphics engine support (TU11x pending)
 - Page kind mapping for turing
 - 10-bit LUT support
 - GP10B Tegra fixes
 - HD audio regression fix
 
 hisilicon/hibmc:
 - use generic fbdev code and helpers
 
 rockchip:
 - dsi/px30 support
 
 virtio:
 - fb damage support
 - static some functions
 
 vc4:
 - use dma_resv lock wrappers
 
 msm:
 - use dma_resv lock wrappers
 - sc7180 display + DSI support
 - a618 support
 - UBWC support improvements
 
 vmwgfx:
 - updates + new logging uapi
 
 exynos:
 - enable/disable callback cleanups
 
 etnaviv:
 - use dma_resv lock wrappers
 
 atmel-hlcdc:
 - clock fixes
 
 mediatek:
 - cmdq support
 - non-smooth cursor fixes
 - ctm property support
 
 sun4i:
 - suspend support
 - A64 mipi dsi support
 
 rcar-du:
 - Color management module support
 - LVDS encoder dual-link support
 - R8A77980 support
 
 analogic:
 - add support for an6345
 
 ast:
 - atomic modeset support
 - primary plane garbage fix
 
 arcgpu:
 - fixes for fourcc handling
 
 tegra:
 - minor fixes and improvments
 
 mcde:
 - vblank support
 
 meson:
 - OSD1 plane AFBC commit
 
 gma500:
 - add pageflip support
 - reomve global drm_dev
 
 komeda:
 - tweak debugfs output
 - d32 support
 - runtime PM suppotr
 
 udl:
 - use generic shmem helpers
 - cleanup and fixes
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Merge tag 'drm-next-2020-01-30' of git://anongit.freedesktop.org/drm/drm

Pull drm updates from Davbe Airlie:
 "This is the main pull request for graphics for 5.6. Usual selection of
  changes all over.

  I've got one outstanding vmwgfx pull that touches mm so kept it
  separate until after all of this lands. I'll try and get it to you
  soon after this, but it might be early next week (nothing wrong with
  code, just my schedule is messy)

  This also hits a lot of fbdev drivers with some cleanups.

  Other notables:
   - vulkan timeline semaphore support added to syncobjs
   - nouveau turing secureboot/graphics support
   - Displayport MST display stream compression support

  Detailed summary:

  uapi:
   - dma-buf heaps added (and fixed)
   - command line add support for panel oreientation
   - command line allow overriding penguin count

  drm:
   - mipi dsi definition updates
   - lockdep annotations for dma_resv
   - remove dma-buf kmap/kunmap support
   - constify fb_ops in all fbdev drivers
   - MST fix for daisy chained hotplug-
   - CTA-861-G modes with VIC >= 193 added
   - fix drm_panel_of_backlight export
   - LVDS decoder support
   - more device based logging support
   - scanline alighment for dumb buffers
   - MST DSC helpers

  scheduler:
   - documentation fixes
   - job distribution improvements

  panel:
   - Logic PD type 28 panel support
   - Jimax8729d MIPI-DSI
   - igenic JZ4770
   - generic DSI devicetree bindings
   - sony acx424AKP panel
   - Leadtek LTK500HD1829
   - xinpeng XPP055C272
   - AUO B116XAK01
   - GiantPlus GPM940B0
   - BOE NV140FHM-N49
   - Satoz SAT050AT40H12R2
   - Sharp LS020B1DD01D panels.

  ttm:
   - use blocking WW lock

  i915:
   - hw/uapi state separation
   - Lock annotation improvements
   - selftest improvements
   - ICL/TGL DSI VDSC support
   - VBT parsing improvments
   - Display refactoring
   - DSI updates + fixes
   - HDCP 2.2 for CFL
   - CML PCI ID fixes
   - GLK+ fbc fix
   - PSR fixes
   - GEN/GT refactor improvments
   - DP MST fixes
   - switch context id alloc to xarray
   - workaround updates
   - LMEM debugfs support
   - tiled monitor fixes
   - ICL+ clock gating programming removed
   - DP MST disable sequence fixed
   - LMEM discontiguous object maps
   - prefaulting for discontiguous objects
   - use LMEM for dumb buffers if possible
   - add LMEM mmap support

  amdgpu:
   - enable sync object timelines for vulkan
   - MST atomic routines
   - enable MST DSC support
   - add DMCUB display microengine support
   - DC OEM i2c support
   - Renoir DC fixes
   - Initial HDCP 2.x support
   - BACO support for Arcturus
   - Use BACO for runtime PM power save
   - gfxoff on navi10
   - gfx10 golden updates and fixes
   - DCN support on POWER
   - GFXOFF for raven1 refresh
   - MM engine idle handlers cleanup
   - 10bpc EDP panel fixes
   - renoir watermark fixes
   - SR-IOV fixes
   - Arcturus VCN fixes
   - GDDR6 training fixes
   - freesync fixes
   - Pollock support

  amdkfd:
   - unify more codepath with amdgpu
   - use KIQ to setup HIQ rather than MMIO

  radeon:
   - fix vma fault handler race
   - PPC DMA fix
   - register check fixes for r100/r200

  nouveau:
   - mmap_sem vs dma_resv fix
   - rewrite the ACR secure boot code for Turing
   - TU10x graphics engine support (TU11x pending)
   - Page kind mapping for turing
   - 10-bit LUT support
   - GP10B Tegra fixes
   - HD audio regression fix

  hisilicon/hibmc:
   - use generic fbdev code and helpers

  rockchip:
   - dsi/px30 support

  virtio:
   - fb damage support
   - static some functions

  vc4:
   - use dma_resv lock wrappers

  msm:
   - use dma_resv lock wrappers
   - sc7180 display + DSI support
   - a618 support
   - UBWC support improvements

  vmwgfx:
   - updates + new logging uapi

  exynos:
   - enable/disable callback cleanups

  etnaviv:
   - use dma_resv lock wrappers

  atmel-hlcdc:
   - clock fixes

  mediatek:
   - cmdq support
   - non-smooth cursor fixes
   - ctm property support

  sun4i:
   - suspend support
   - A64 mipi dsi support

  rcar-du:
   - Color management module support
   - LVDS encoder dual-link support
   - R8A77980 support

  analogic:
   - add support for an6345

  ast:
   - atomic modeset support
   - primary plane garbage fix

  arcgpu:
   - fixes for fourcc handling

  tegra:
   - minor fixes and improvments

  mcde:
   - vblank support

  meson:
   - OSD1 plane AFBC commit

  gma500:
   - add pageflip support
   - reomve global drm_dev

  komeda:
   - tweak debugfs output
   - d32 support
   - runtime PM suppotr

  udl:
   - use generic shmem helpers
   - cleanup and fixes"

* tag 'drm-next-2020-01-30' of git://anongit.freedesktop.org/drm/drm: (1998 commits)
  drm/nouveau/fb/gp102-: allow module to load even when scrubber binary is missing
  drm/nouveau/acr: return error when registering LSF if ACR not supported
  drm/nouveau/disp/gv100-: not all channel types support reporting error codes
  drm/nouveau/disp/nv50-: prevent oops when no channel method map provided
  drm/nouveau: support synchronous pushbuf submission
  drm/nouveau: signal pending fences when channel has been killed
  drm/nouveau: reject attempts to submit to dead channels
  drm/nouveau: zero vma pointer even if we only unreference it rather than free
  drm/nouveau: Add HD-audio component notifier support
  drm/nouveau: fix build error without CONFIG_IOMMU_API
  drm/nouveau/kms/nv04: remove set but not used variable 'width'
  drm/nouveau/kms/nv50: remove set but not unused variable 'nv_connector'
  drm/nouveau/mmu: fix comptag memory leak
  drm/nouveau/gr/gp10b: Use gp100_grctx and gp100_gr_zbc
  drm/nouveau/pmu/gm20b,gp10b: Fix Falcon bootstrapping
  drm/exynos: Rename Exynos to lowercase
  drm/exynos: change callback names
  drm/mst: Don't do atomic checks over disabled managers
  drm/amdgpu: add the lost mutex_init back
  drm/amd/display: skip opp blank or unblank if test pattern enabled
  ...
2020-01-30 08:04:01 -08:00
SeongJae Park 060eabe8fb xenbus/backend: Protect xenbus callback with lock
A driver's 'reclaim_memory' callback can race with 'probe' or 'remove'
because it will be called whenever memory pressure is detected.  To
avoid such race, this commit embeds a spinlock in each 'xenbus_device'
and make 'xenbus' to hold the lock while the corresponded callbacks are
running.

Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: SeongJae Park <sjpark@amazon.de>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-01-29 07:35:49 -06:00
SeongJae Park 8a105678fb xenbus/backend: Add memory pressure handler callback
Granting pages consumes backend system memory.  In systems configured
with insufficient spare memory for those pages, it can cause a memory
pressure situation.  However, finding the optimal amount of the spare
memory is challenging for large systems having dynamic resource
utilization patterns.  Also, such a static configuration might lack
flexibility.

To mitigate such problems, this commit adds a memory reclaim callback to
'xenbus_driver'.  If a memory pressure is detected, 'xenbus' requests
every backend driver to volunarily release its memory.

Note that it would be able to improve the callback facility for more
sophisticated handlings of general pressures.  For example, it would be
possible to monitor the memory consumption of each device and issue the
release requests to only devices which causing the pressure.  Also, the
callback could be extended to handle not only memory, but general
resources.  Nevertheless, this version of the implementation defers such
sophisticated goals as a future work.

Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: SeongJae Park <sjpark@amazon.de>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-01-29 07:35:49 -06:00
Boris Ostrovsky 9293724192 xen/gntdev: Do not use mm notifiers with autotranslating guests
Commit d3eeb1d77c ("xen/gntdev: use mmu_interval_notifier_insert")
missed a test for use_ptemod when calling mmu_interval_read_begin(). Fix
that.

Fixes: d3eeb1d77c ("xen/gntdev: use mmu_interval_notifier_insert")
CC: stable@vger.kernel.org # 5.5
Reported-by: Ilpo Järvinen <ilpo.jarvinen@cs.helsinki.fi>
Tested-by: Ilpo Järvinen <ilpo.jarvinen@cs.helsinki.fi>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Acked-by: Juergen Gross <jgross@suse.com>
2020-01-28 12:22:48 -06:00
Juergen Gross eda4eabf86 xen/balloon: Support xend-based toolstack take two
Commit 3aa6c19d2f ("xen/balloon: Support xend-based toolstack")
tried to fix a regression with running on rather ancient Xen versions.
Unfortunately the fix was based on the assumption that xend would
just use another Xenstore node, but in reality only some downstream
versions of xend are doing that. The upstream xend does not write
that Xenstore node at all, so the problem must be fixed in another
way.

The easiest way to achieve that is to fall back to the behavior
before commit 96edd61dcf ("xen/balloon: don't online new memory
initially") in case the static memory maximum can't be read.

This is achieved by setting static_max to the current number of
memory pages known by the system resulting in target_diff becoming
zero.

Fixes: 3aa6c19d2f ("xen/balloon: Support xend-based toolstack")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: <stable@vger.kernel.org> # 4.13
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-01-22 08:58:16 -06:00
Dave Airlie 3d4743131b Linux 5.5-rc7
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Backmerge v5.5-rc7 into drm-next

msm needs 5.5-rc4, go to the latest.

Signed-off-by: Dave Airlie <airlied@redhat.com>
2020-01-20 11:42:57 +10:00
Marek Marczykowski-Górecki 476878e4b2 xen-pciback: optionally allow interrupt enable flag writes
QEMU running in a stubdom needs to be able to set INTX_DISABLE, and the
MSI(-X) enable flags in the PCI config space. This adds an attribute
'allow_interrupt_control' which when set for a PCI device allows writes
to this flag(s). The toolstack will need to set this for stubdoms.
When enabled, guest (stubdomain) will be allowed to set relevant enable
flags, but only one at a time - i.e. it refuses to enable more than one
of INTx, MSI, MSI-X at a time.

This functionality is needed only for config space access done by device
model (stubdomain) serving a HVM with the actual PCI device. It is not
necessary and unsafe to enable direct access to those bits for PV domain
with the device attached. For PV domains, there are separate protocol
messages (XEN_PCI_OP_{enable,disable}_{msi,msix}) for this purpose.
Those ops in addition to setting enable bits, also configure MSI(-X) in
dom0 kernel - which is undesirable for PCI passthrough to HVM guests.

This should not introduce any new security issues since a malicious
guest (or stubdom) can already generate MSIs through other ways, see
[1] page 8. Additionally, when qemu runs in dom0, it already have direct
access to those bits.

This is the second iteration of this feature. First was proposed as a
direct Xen interface through a new hypercall, but ultimately it was
rejected by the maintainer, because of mixing pciback and hypercalls for
PCI config space access isn't a good design. Full discussion at [2].

[1]: https://invisiblethingslab.com/resources/2011/Software%20Attacks%20on%20Intel%20VT-d.pdf
[2]: https://xen.markmail.org/thread/smpgpws4umdzizze

[part of the commit message and sysfs handling]
Signed-off-by: Simon Gaiser <simon@invisiblethingslab.com>
[the rest]
Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
[boris: A few small changes suggested by Roger, some formatting changes]
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-01-15 16:50:13 -06:00
Ingo Molnar 1e5f8a3085 Linux 5.5-rc3
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Merge tag 'v5.5-rc3' into sched/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-25 10:41:37 +01:00
Linus Torvalds 62af608b4b xen: branch for v5.5-rc3
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Merge tag 'for-linus-5.5b-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen fixes from Juergen Gross:
 "This contains two cleanup patches and a small series for supporting
  reloading the Xen block backend driver"

* tag 'for-linus-5.5b-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/grant-table: remove multiple BUG_ON on gnttab_interface
  xen-blkback: support dynamic unbind/bind
  xen/interface: re-define FRONT/BACK_RING_ATTACH()
  xenbus: limit when state is forced to closed
  xenbus: move xenbus_dev_shutdown() into frontend code...
  xen/blkfront: Adjust indentation in xlvbd_alloc_gendisk
2019-12-21 06:24:56 -08:00
Aditya Pakki d6bd6cf9fe xen/grant-table: remove multiple BUG_ON on gnttab_interface
gnttab_request_version() always sets the gnttab_interface variable
and the assertions to check for empty gnttab_interface is unnecessary.
The patch eliminates multiple such assertions.

Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2019-12-20 13:54:56 +01:00
Paul Durrant 672b7763cb xenbus: limit when state is forced to closed
If a driver probe() fails then leave the xenstore state alone. There is no
reason to modify it as the failure may be due to transient resource
allocation issues and hence a subsequent probe() may succeed.

If the driver supports re-binding then only force state to closed during
remove() only in the case when the toolstack may need to clean up. This can
be detected by checking whether the state in xenstore has been set to
closing prior to device removal.

NOTE: Re-bind support is indicated by new boolean in struct xenbus_driver,
      which defaults to false. Subsequent patches will add support to
      some backend drivers.

Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2019-12-20 13:44:38 +01:00
Paul Durrant c534374ecf xenbus: move xenbus_dev_shutdown() into frontend code...
...and make it static

xenbus_dev_shutdown() is seemingly intended to cause clean shutdown of PV
frontends when a guest is rebooted. Indeed the function waits for a
conpletion which is only set by a call to xenbus_frontend_closed().

This patch removes the shutdown() method from backends and moves
xenbus_dev_shutdown() from xenbus_probe.c into xenbus_probe_frontend.c,
renaming it appropriately and making it static.

NOTE: In the case where the backend is running in a driver domain, the
      toolstack should have already terminated any frontends that may be
      using it (since Xen does not support re-startable PV driver domains)
      so xenbus_dev_shutdown() should never be called.

Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2019-12-20 13:44:35 +01:00
Daniel Vetter 6c56e8adc0 drm-misc-next for v5.6:
UAPI Changes:
 - Add support for DMA-BUF HEAPS.
 
 Cross-subsystem Changes:
 - mipi dsi definition updates, pulled into drm-intel as well.
 - Add lockdep annotations for dma_resv vs mmap_sem and fs_reclaim.
 - Remove support for dma-buf kmap/kunmap.
 - Constify fb_ops in all fbdev drivers, including drm drivers and drm-core, and media as well.
 
 Core Changes:
 - Small cleanups to ttm.
 - Fix SCDC definition.
 - Assorted cleanups to core.
 - Add todo to remove load/unload hooks, and use generic fbdev emulation.
 - Assorted documentation updates.
 - Use blocking ww lock in ttm fault handler.
 - Remove drm_fb_helper_fbdev_setup/teardown.
 - Warning fixes with W=1 for atomic.
 - Use drm_debug_enabled() instead of drm_debug flag testing in various drivers.
 - Fallback to nontiled mode in fbdev emulation when not all tiles are present. (Later on reverted)
 - Various kconfig indentation fixes in core and drivers.
 - Fix freeing transactions in dp-mst correctly.
 - Sean Paul is steping down as core maintainer. :-(
 - Add lockdep annotations for atomic locks vs dma-resv.
 - Prevent use-after-free for a bad job in drm_scheduler.
 - Fill out all block sizes in the P01x and P210 definitions.
 - Avoid division by zero in drm/rect, and fix bounds.
 - Add drm/rect selftests.
 - Add aspect ratio and alternate clocks for HDMI 4k modes.
 - Add todo for drm_framebuffer_funcs and fb_create cleanup.
 - Drop DRM_AUTH for prime import/export ioctls.
 - Clear DP-MST payload id tables downstream when initializating.
 - Fix for DSC throughput definition.
 - Add extra FEC definitions.
 - Fix fake offset in drm_gem_object_funs.mmap.
 - Stop using encoder->bridge in core directly
 - Handle bridge chaining slightly better.
 - Add backlight support to drm/panel, and use it in many panel drivers.
 - Increase max number of y420 modes from 128 to 256, as preparation to add the new modes.
 
 Driver Changes:
 - Small fixes all over.
 - Fix documentation in vkms.
 - Fix mmap_sem vs dma_resv in nouveau.
 - Small cleanup in komeda.
 - Add page flip support in gma500 for psb/cdv.
 - Add ddc symlink in the connector sysfs directory for many drivers.
 - Add support for analogic an6345, and fix small bugs in it.
 - Add atomic modesetting support to ast.
 - Fix radeon fault handler VMA race.
 - Switch udl to use generic shmem helpers.
 - Unconditional vblank handling for mcde.
 - Miscellaneous fixes to mcde.
 - Tweak debug output from komeda using debugfs.
 - Add gamma and color transform support to komeda for DOU-IPS.
 - Add support for sony acx424AKP panel.
 - Various small cleanups to gma500.
 - Use generic fbdev emulation in udl, and replace udl_framebuffer with generic implementation.
 - Add support for Logic PD Type 28 panel.
 - Use drm_panel_* wrapper functions in exynos/tegra/msm.
 - Add devicetree bindings for generic DSI panels.
 - Don't include drm_pci.h directly in many drivers.
 - Add support for begin/end_cpu_access in udmabuf.
 - Stop using drm_get_pci_dev in gma500 and mga200.
 - Fixes to UDL damage handling, and use dma_buf_begin/end_cpu_access.
 - Add devfreq thermal support to panfrost.
 - Fix hotplug with daisy chained monitors by removing VCPI when disabling topology manager.
 - meson: Add support for OSD1 plane AFBC commit.
 - Stop displaying garbage when toggling ast primary plane on/off.
 - More cleanups and fixes to UDL.
 - Add D32 suport to komeda.
 - Remove globle copy of drm_dev in gma500.
 - Add support for Boe Himax8279d MIPI-DSI LCD panel.
 - Add support for ingenic JZ4770 panel.
 - Small null pointer deference fix in ingenic.
 - Remove support for the special tfp420 driver, as there is a generic way to do it.
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Merge tag 'drm-misc-next-2019-12-16' of git://anongit.freedesktop.org/drm/drm-misc into drm-next

drm-misc-next for v5.6:

UAPI Changes:
- Add support for DMA-BUF HEAPS.

Cross-subsystem Changes:
- mipi dsi definition updates, pulled into drm-intel as well.
- Add lockdep annotations for dma_resv vs mmap_sem and fs_reclaim.
- Remove support for dma-buf kmap/kunmap.
- Constify fb_ops in all fbdev drivers, including drm drivers and drm-core, and media as well.

Core Changes:
- Small cleanups to ttm.
- Fix SCDC definition.
- Assorted cleanups to core.
- Add todo to remove load/unload hooks, and use generic fbdev emulation.
- Assorted documentation updates.
- Use blocking ww lock in ttm fault handler.
- Remove drm_fb_helper_fbdev_setup/teardown.
- Warning fixes with W=1 for atomic.
- Use drm_debug_enabled() instead of drm_debug flag testing in various drivers.
- Fallback to nontiled mode in fbdev emulation when not all tiles are present. (Later on reverted)
- Various kconfig indentation fixes in core and drivers.
- Fix freeing transactions in dp-mst correctly.
- Sean Paul is steping down as core maintainer. :-(
- Add lockdep annotations for atomic locks vs dma-resv.
- Prevent use-after-free for a bad job in drm_scheduler.
- Fill out all block sizes in the P01x and P210 definitions.
- Avoid division by zero in drm/rect, and fix bounds.
- Add drm/rect selftests.
- Add aspect ratio and alternate clocks for HDMI 4k modes.
- Add todo for drm_framebuffer_funcs and fb_create cleanup.
- Drop DRM_AUTH for prime import/export ioctls.
- Clear DP-MST payload id tables downstream when initializating.
- Fix for DSC throughput definition.
- Add extra FEC definitions.
- Fix fake offset in drm_gem_object_funs.mmap.
- Stop using encoder->bridge in core directly
- Handle bridge chaining slightly better.
- Add backlight support to drm/panel, and use it in many panel drivers.
- Increase max number of y420 modes from 128 to 256, as preparation to add the new modes.

Driver Changes:
- Small fixes all over.
- Fix documentation in vkms.
- Fix mmap_sem vs dma_resv in nouveau.
- Small cleanup in komeda.
- Add page flip support in gma500 for psb/cdv.
- Add ddc symlink in the connector sysfs directory for many drivers.
- Add support for analogic an6345, and fix small bugs in it.
- Add atomic modesetting support to ast.
- Fix radeon fault handler VMA race.
- Switch udl to use generic shmem helpers.
- Unconditional vblank handling for mcde.
- Miscellaneous fixes to mcde.
- Tweak debug output from komeda using debugfs.
- Add gamma and color transform support to komeda for DOU-IPS.
- Add support for sony acx424AKP panel.
- Various small cleanups to gma500.
- Use generic fbdev emulation in udl, and replace udl_framebuffer with generic implementation.
- Add support for Logic PD Type 28 panel.
- Use drm_panel_* wrapper functions in exynos/tegra/msm.
- Add devicetree bindings for generic DSI panels.
- Don't include drm_pci.h directly in many drivers.
- Add support for begin/end_cpu_access in udmabuf.
- Stop using drm_get_pci_dev in gma500 and mga200.
- Fixes to UDL damage handling, and use dma_buf_begin/end_cpu_access.
- Add devfreq thermal support to panfrost.
- Fix hotplug with daisy chained monitors by removing VCPI when disabling topology manager.
- meson: Add support for OSD1 plane AFBC commit.
- Stop displaying garbage when toggling ast primary plane on/off.
- More cleanups and fixes to UDL.
- Add D32 suport to komeda.
- Remove globle copy of drm_dev in gma500.
- Add support for Boe Himax8279d MIPI-DSI LCD panel.
- Add support for ingenic JZ4770 panel.
- Small null pointer deference fix in ingenic.
- Remove support for the special tfp420 driver, as there is a generic way to do it.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/ba73535a-9334-5302-2e1f-5208bd7390bd@linux.intel.com
2019-12-17 13:57:54 +01:00
Linus Torvalds b01d7cb41f xen: branch for v5.5-rc2
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Merge tag 'for-linus-5.5b-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen fixes from Juergen Gross:
 "Two fixes: one for a resource accounting bug in some configurations
  and a fix for another patch which went into rc1"

* tag 'for-linus-5.5b-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/balloon: fix ballooned page accounting without hotplug enabled
  xen-blkback: prevent premature module unload
2019-12-15 12:24:44 -08:00