Today 4 architectures set ARCH_SUPPORTS_MEMORY_FAILURE (arm64, parisc,
powerpc, and x86), while 4 other architectures set __ARCH_SI_TRAPNO
(alpha, metag, sparc, and tile).  These two sets of architectures do
not interesect so remove the trapno paramater to remove confusion.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

There are so many places that build struct siginfo by hand that at
least one of them is bound to get it wrong.  A handful of cases in the
kernel arguably did just that when using the errno field of siginfo to
pass no errno values to userspace.  The usage is limited to a single
si_code so at least does not mess up anything else.

Encapsulate this questionable pattern in a helper function so
that the userspace ABI is preserved.

Update all of the places that use this pattern to use the new helper
function.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

signal_code is always TRAP_HWBKPT
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

The function clear_siginfo is just a nice wrapper around memset so
this results in no functional change.  This change makes mistakes
a little more difficult and it makes it clearer what is going on.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

The siginfo structure has all manners of holes with the result that a
structure initializer is not guaranteed to initialize all of the bits.
As we have to copy the structure to userspace don't even try to use
a structure initializer.  Instead use clear_siginfo followed by initializing
selected fields.  This gives a guarantee that uninitialized kernel memory
is not copied to userspace.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Instead of jumpping while !is_compat_task placee all of the code
inside of an if (is_compat_task) block.  This allows the int i
variable to be properly limited to the compat block no matter how the
rest of ptrace_hbptriggered changes.

In a following change a non-variable declaration will preceed
was made independent to ensure the code is easy to review.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Among the existing architecture specific versions of
copy_siginfo_to_user32 there are several different implementation
problems.  Some architectures fail to handle all of the cases in in
the siginfo union.  Some architectures perform a blind copy of the
siginfo union when the si_code is negative.  A blind copy suggests the
data is expected to be in 32bit siginfo format, which means that
receiving such a signal via signalfd won't work, or that the data is
in 64bit siginfo and the code is copying nonsense to userspace.

Create a single instance of copy_siginfo_to_user32 that all of the
architectures can share, and teach it to handle all of the cases in
the siginfo union correctly, with the assumption that siginfo is
stored internally to the kernel is 64bit siginfo format.

A special case is made for x86 x32 format.  This is needed as presence
of both x32 and ia32 on x86_64 results in two different 32bit signal
formats.  By allowing this small special case there winds up being
exactly one code base that needs to be maintained between all of the
architectures.  Vastly increasing the testing base and the chances of
finding bugs.

As the x86 copy of copy_siginfo_to_user32 the call of the x86
signal_compat_build_tests were moved into sigaction_compat_abi, so
that they will keep running.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

The function copy_siginfo_from_user32 is used for two things, in ptrace
since the dawn of siginfo for arbirarily modifying a signal that
user space sees, and in sigqueueinfo to send a signal with arbirary
siginfo data.

Create a single copy of copy_siginfo_from_user32 that all architectures
share, and teach it to handle all of the cases in the siginfo union.

In the generic version of copy_siginfo_from_user32 ensure that all
of the fields in siginfo are initialized so that the siginfo structure
can be safely copied to userspace if necessary.

When copying the embedded sigval union copy the si_int member.  That
ensures the 32bit values passes through the kernel unchanged.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Nothing tests this define so just remove it.

I suspect the intention was to make the uid field in siginfo 16bit
however I can't find any code that ever tested this defined, and
even if it did it the layout has been this way for 8 years so
changing it now would break the ABI with userspace.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Having si_codes in many different files simply encourages duplicate definitions
that can cause problems later.  To avoid that merge the blackfin specific si_codes
into uapi/asm-generic/siginfo.h

Update copy_siginfo_to_user to copy with the absence of BUS_MCEERR_AR that blackfin
defines to be something else.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Having si_codes in many different files simply encourages duplicate definitions
that can cause problems later.  To avoid that merge the tile specific si_codes
into uapi/asm-generic/siginfo.h
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Having si_codes in many different files simply encourages duplicate definitions
that can cause problems later.  To avoid that merce the frv specific si_codes
into uapi/asm-generic/siginfo.h

This allows the removal of arch/frv/uapi/include/asm/siginfo.h as the last
last meaningful definition it held was FPE_MDAOVF.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Having si_codes in many different files simply encourages duplicate
definitions that can cause problems later.  To avoid that merge the
ia64 specific si_codes into uapi/asm-generic/siginfo.h

Update the sanity checks in arch/x86/kernel/signal_compat.c to expect
the now lager NSIGILL and NSIGFPE.  As nothing excpe the larger count
is exposed on x86 no additional code needs to be updated.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

NSIGTRAP is 4 in the generic siginfo and powerpc just undefines
NSGTRAP and redefine it as 4.  That accomplishes nothing so remove
the duplication.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

--EWB Added #ifdef CONFIG_X86_X32_ABI to arch/x86/kernel/signal_compat.c
      Changed #ifdef CONFIG_X86_X32 to #ifdef CONFIG_X86_X32_ABI in
      linux/compat.h

      CONFIG_X86_X32 is set when the user requests X32 support.

      CONFIG_X86_X32_ABI is set when the user requests X32 support
      and the tool-chain has X32 allowing X32 support to be built.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>

... having taught the latter that si_errno and si_code might be
swapped.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>

Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

... at a cost of added small ifdef __ia64__ in asm-generic siginfo.h,
that is.

-- EWB Corrected the comment on _flags to reflect the move
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

We have never passed either field to or from userspace so just remove them.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

SEGV_PKUERR is a signal specific si_code which happens to have the
same numeric value as several others: BUS_MCEERR_AR, ILL_ILLTRP,
FPE_FLTOVF, TRAP_HWBKPT, CLD_TRAPPED, POLL_ERR, SEGV_THREAD_ID,
as such it is not safe to just test the si_code the signal number
must also be tested to prevent a false positive in fill_sig_info_pkey.

I found this error by inspection, and BUS_MCEERR_AR appears to
be a real candidate for confusion.  So pass in si_signo and fix it.

Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Fixes: 019132ff ("x86/mm/pkeys: Fill in pkey field in siginfo")
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Setting si_code to 0 is the same a setting si_code to SI_USER which is definitely
not correct.  With si_code set to SI_USER si_pid and si_uid will be copied to
userspace instead of si_addr.  Which is very wrong.

So fix this by using a sensible si_code (SEGV_MAPERR) for this failure.

Cc: stable@vger.kernel.org
Fixes: b920de1b ("mn10300: add the MN10300/AM33 architecture to the kernel")
Cc: David Howells <dhowells@redhat.com>
Cc: Masakazu Urade <urade.masakazu@jp.panasonic.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Setting si_code to 0 results in a userspace seeing an si_code of 0.
This is the same si_code as SI_USER.  Posix and common sense requires
that SI_USER not be a signal specific si_code.  As such this use of 0
for the si_code is a pretty horribly broken ABI.

Further use of si_code == 0 guaranteed that copy_siginfo_to_user saw a
value of __SI_KILL and now sees a value of SIL_KILL with the result
that uid and pid fields are copied and which might copying the si_addr
field by accident but certainly not by design.  Making this a very
flakey implementation.

Utilizing FPE_FIXME, siginfo_layout will now return SIL_FAULT and the
appropriate fields will be reliably copied.

Possible ABI fixes includee:
- Send the signal without siginfo
- Don't generate a signal
- Possibly assign and use an appropriate si_code
- Don't handle cases which can't happen

Cc: Russell King <rmk@flint.arm.linux.org.uk>
Cc: linux-arm-kernel@lists.infradead.org
Ref: 451436b7bbb2 ("[ARM] Add support code for ARM hardware vector floating point")
History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.gitSigned-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Setting si_code to 0 results in a userspace seeing an si_code of 0.
This is the same si_code as SI_USER.  Posix and common sense requires
that SI_USER not be a signal specific si_code.  As such this use of 0
for the si_code is a pretty horribly broken ABI.

Further use of si_code == 0 guaranteed that copy_siginfo_to_user saw a
value of __SI_KILL and now sees a value of SIL_KILL with the result
that uid and pid fields are copied and which might copying the si_addr
field by accident but certainly not by design.  Making this a very
flakey implementation.

Utilizing FPE_FIXME, BUS_FIXME, TRAP_FIXME siginfo_layout will now return
SIL_FAULT and the appropriate fields will be reliably copied.

But folks this is a new and unique kind of bad.  This is massively
untested code bad.  This is inventing new and unique was to get
siginfo wrong bad.  This is don't even think about Posix or what
siginfo means bad.  This is lots of eyeballs all missing the fact
that the code does the wrong thing bad.  This is getting stuck
and keep making the same mistake bad.

I really hope we can find a non userspace breaking fix for this on a
port as new as arm64.

Possible ABI fixes include:
- Send the signal without siginfo
- Don't generate a signal
- Possibly assign and use an appropriate si_code
- Don't handle cases which can't happen

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Tyler Baicar <tbaicar@codeaurora.org>
Cc: James Morse <james.morse@arm.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Nicolas Pitre <nico@linaro.org>
Cc: Olof Johansson <olof@lixom.net>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-arm-kernel@lists.infradead.org
Ref: 53631b54 ("arm64: Floating point and SIMD")
Ref: 32015c23 ("arm64: exception: handle Synchronous External Abort")
Ref: 1d18c47c ("arm64: MMU fault handling and page table management")
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Setting si_code to 0 results in a userspace seeing an si_code of 0.
This is the same si_code as SI_USER.  Posix and common sense requires
that SI_USER not be a signal specific si_code.  As such this use of 0
for the si_code is a pretty horribly broken ABI.

Further use of si_code == 0 guaranteed that copy_siginfo_to_user saw a
value of __SI_KILL and now sees a value of SIL_KILL with the result
that uid and pid fields are copied and which might copying the si_addr
field by accident but certainly not by design.  Making this a very
flakey implementation.

Utilizing FPE_FIXME and TRAP_FIXME, siginfo_layout() will now return
SIL_FAULT and the appropriate fields will be reliably copied.

Possible ABI fixes includee:
- Send the signal without siginfo
- Don't generate a signal
- Possibly assign and use an appropriate si_code
- Don't handle cases which can't happen
Cc: Paul Mackerras <paulus@samba.org>
Cc: Kumar Gala <kumar.gala@freescale.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc:  linuxppc-dev@lists.ozlabs.org
Ref: 9bad068c24d7 ("[PATCH] ppc32: support for e500 and 85xx")
Ref: 0ed70f6105ef ("PPC32: Provide proper siginfo information on various exceptions.")
History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.gitSigned-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Setting si_code to 0 results in a userspace seeing an si_code of 0.
This is the same si_code as SI_USER.  Posix and common sense requires
that SI_USER not be a signal specific si_code.  As such this use of 0
for the si_code is a pretty horribly broken ABI.

Further use of si_code == 0 guaranteed that copy_siginfo_to_user saw a
value of __SI_KILL and now sees a value of SIL_KILL with the result
hat uid and pid fields are copied and which might copying the si_addr
field by accident but certainly not by design.  Making this a very
flakey implementation.

Utilizing FPE_FIXME siginfo_layout will now return SIL_FAULT and the
appropriate fields will reliably be copied.

Possible ABI fixes includee:
  - Send the signal without siginfo
  - Don't generate a signal
  - Possibly assign and use an appropriate si_code
  - Don't handle cases which can't happen

Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-metag@vger.kernel.org
Ref: ac919f08 ("metag: Traps")
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Setting si_code to 0 results in a userspace seeing an si_code of 0.
This is the same si_code as SI_USER.  Posix and common sense requires
that SI_USER not be a signal specific si_code.  As such this use of 0
for the si_code is a pretty horribly broken ABI.

Further use of si_code == 0 guaranteed that copy_siginfo_to_user saw a
value of __SI_KILL and now sees a value of SIL_KILL with the result
that uid and pid fields are copied and which might copying the si_addr
field by accident but certainly not by design.  Making this a very
flakey implementation.

Utilizing FPE_FIXME siginfo_layout will now return SIL_FAULT and the
appropriate fields will reliably be copied.

This bug is 13 years old and parsic machines are no longer being built
so I don't know if it possible or worth fixing it.  But it is at least
worth documenting this so other architectures don't make the same
mistake.

Possible ABI fixes includee:
  - Send the signal without siginfo
  - Don't generate a signal
  - Possibly assign and use an appropriate si_code
  - Don't handle cases which can't happen

Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
Ref: 313c01d3e3fd ("[PATCH] PA-RISC update for 2.6.0")
Histroy Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.gitSigned-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

While reviewing the signal sending on openrisc the do_unaligned_access
function stood out because it is obviously wrong.  A comment about an
si_code set above when actually si_code is never set.  Leading to a
random si_code being sent to userspace in the event of an unaligned
access.

Looking further SIGBUS BUS_ADRALN is the proper pair of signal and
si_code to send for an unaligned access. That is what other
architectures do and what is required by posix.

Given that do_unaligned_access is broken in a way that no one can be
relying on it on openrisc fix the code to just do the right thing.

Cc: stable@vger.kernel.org
Fixes: 769a8a96 ("OpenRISC: Traps")
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: openrisc@lists.librecores.org
Acked-by: NStafford Horne <shorne@gmail.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Set si_signo.

Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: linux-sh@vger.kernel.org
Cc: stable@vger.kernel.org
Fixes: 0983b318 ("sh: Wire up division and address error exceptions on SH-2A.")
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Andy prefers to be paranoid about the pagetable free in the error path of
write_ldt(). Make it conditional and warn whenever the installment of a
secondary LDT fails.
Requested-by: NAndy Lutomirski <luto@amacapital.net>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

The error path in write_ldt() tries to free 'old_ldt' instead of the newly
allocated 'new_ldt', resulting in a memory leak. It also misses to clean up a
half populated LDT pagetable, which is not a leak as it gets cleaned up
when the process exits.

Free both the potentially half populated LDT pagetable and the newly
allocated LDT struct. This can be done unconditionally because once an LDT
is mapped subsequent maps will succeed, because the PTE page is already
populated and the two LDTs fit into that single page.
Reported-by: NMathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linuxfoundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Fixes: f55f0501 ("x86/pti: Put the LDT in its own PGD if PTI is on")
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1712311121340.1899@nanosSigned-off-by: NIngo Molnar <mingo@kernel.org>

The preempt_disable/enable() pair in __native_flush_tlb() was added in
commit:

  5cf0791d ("x86/mm: Disable preemption during CR3 read+write")

... to protect the UP variant of flush_tlb_mm_range().

That preempt_disable/enable() pair should have been added to the UP variant
of flush_tlb_mm_range() instead.

The UP variant was removed with commit:

  ce4a4e56 ("x86/mm: Remove the UP asm/tlbflush.h code, always use the (formerly) SMP code")

... but the preempt_disable/enable() pair stayed around.

The latest change to __native_flush_tlb() in commit:

  6fd166aa ("x86/mm: Use/Fix PCID to optimize user/kernel switches")

... added an access to a per CPU variable outside the preempt disabled
regions, which makes no sense at all. __native_flush_tlb() must always
be called with at least preemption disabled.

Remove the preempt_disable/enable() pair and add a WARN_ON_ONCE() to catch
bad callers independent of the smp_processor_id() debugging.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linuxfoundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20171230211829.679325424@linutronix.deSigned-off-by: NIngo Molnar <mingo@kernel.org>

smpboot_setup_warm_reset_vector() and smpboot_restore_warm_reset_vector()
invoke local_flush_tlb() for no obvious reason.

Digging in history revealed that the original code in the 2.1 era added
those because the code manipulated a swapper_pg_dir pagetable entry. The
pagetable manipulation was removed long ago in the 2.3 timeframe, but the
TLB flush invocations stayed around forever.

Remove them along with the pointless pr_debug()s which come from the same 2.1
change.
Reported-by: NDominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linuxfoundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20171230211829.586548655@linutronix.deSigned-off-by: NIngo Molnar <mingo@kernel.org>

The new reservation mode for interrupts assigns a dummy vector when the
interrupt is allocated and assigns a real vector when the interrupt is
requested. The reservation mode prevents vector pressure when devices with
a large amount of queues/interrupts are initialized, but only a minimal
subset of those queues/interrupts is actually used.

This mode has an issue with MSI interrupts which cannot be masked. If the
driver is not careful or the hardware emits an interrupt before the device
irq is requestd by the driver then the interrupt ends up on the dummy
vector as a spurious interrupt which can cause malfunction of the device or
in the worst case a lockup of the machine.

Change the logic for the reservation mode so that the early activation of
MSI interrupts checks whether:

 - the device is a PCI/MSI device
 - the reservation mode of the underlying irqdomain is activated
 - PCI/MSI masking is globally enabled
 - the PCI/MSI device uses either MSI-X, which supports masking, or
   MSI with the maskbit supported.

If one of those conditions is false, then clear the reservation mode flag
in the irq data of the interrupt and invoke irq_domain_activate_irq() with
the reserve argument cleared. In the x86 vector code, clear the can_reserve
flag in the vector allocation data so a subsequent free_irq() won't create
the same situation again. The interrupt stays assigned to a real vector
until pci_disable_msi() is invoked and all allocations are undone.

Fixes: 4900be83 ("x86/vector/msi: Switch to global reservation mode")
Reported-by: NAlexandru Chirvasitu <achirvasub@gmail.com>
Reported-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Tested-by: NAlexandru Chirvasitu <achirvasub@gmail.com>
Tested-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Dou Liyang <douly.fnst@cn.fujitsu.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Mikael Pettersson <mikpelinux@gmail.com>
Cc: Josh Poulson <jopoulso@microsoft.com>
Cc: Mihai Costache <v-micos@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: linux-pci@vger.kernel.org
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Dexuan Cui <decui@microsoft.com>
Cc: Simon Xiao <sixiao@microsoft.com>
Cc: Saeed Mahameed <saeedm@mellanox.com>
Cc: Jork Loeser <Jork.Loeser@microsoft.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: devel@linuxdriverproject.org
Cc: KY Srinivasan <kys@microsoft.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Sakari Ailus <sakari.ailus@intel.com>,
Cc: linux-media@vger.kernel.org
Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1712291406420.1899@nanos
Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1712291409460.1899@nanos

The 'early' argument of irq_domain_activate_irq() is actually used to
denote reservation mode. To avoid confusion, rename it before abuse
happens.

No functional change.

Fixes: 72491643 ("genirq/irqdomain: Update irq_domain_ops.activate() signature")
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Alexandru Chirvasitu <achirvasub@gmail.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Dou Liyang <douly.fnst@cn.fujitsu.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Mikael Pettersson <mikpelinux@gmail.com>
Cc: Josh Poulson <jopoulso@microsoft.com>
Cc: Mihai Costache <v-micos@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: linux-pci@vger.kernel.org
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Dexuan Cui <decui@microsoft.com>
Cc: Simon Xiao <sixiao@microsoft.com>
Cc: Saeed Mahameed <saeedm@mellanox.com>
Cc: Jork Loeser <Jork.Loeser@microsoft.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: devel@linuxdriverproject.org
Cc: KY Srinivasan <kys@microsoft.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Sakari Ailus <sakari.ailus@intel.com>,
Cc: linux-media@vger.kernel.org

Set the new CAN_RESERVE flag when the initial reservation for an interrupt
happens. The flag is used in a subsequent patch to disable reservation mode
for a certain class of MSI devices.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Tested-by: NAlexandru Chirvasitu <achirvasub@gmail.com>
Tested-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Dou Liyang <douly.fnst@cn.fujitsu.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Mikael Pettersson <mikpelinux@gmail.com>
Cc: Josh Poulson <jopoulso@microsoft.com>
Cc: Mihai Costache <v-micos@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: linux-pci@vger.kernel.org
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Dexuan Cui <decui@microsoft.com>
Cc: Simon Xiao <sixiao@microsoft.com>
Cc: Saeed Mahameed <saeedm@mellanox.com>
Cc: Jork Loeser <Jork.Loeser@microsoft.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: devel@linuxdriverproject.org
Cc: KY Srinivasan <kys@microsoft.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Sakari Ailus <sakari.ailus@intel.com>,
Cc: linux-media@vger.kernel.org

Some of the APIC incarnations are operating in lowest priority delivery
mode. This worked as long as the vector management code allocated the same
vector on all possible CPUs for each interrupt.

Lowest priority delivery mode does not necessarily respect the affinity
setting and may redirect to some other online CPU. This was documented
somewhere in the old code and the conversion to single target delivery
missed to update the delivery mode of the affected APIC drivers which
results in spurious interrupts on some of the affected CPU/Chipset
combinations.

Switch the APIC drivers over to Fixed delivery mode and remove all
leftovers of lowest priority delivery mode.

Switching to Fixed delivery mode is not a problem on these CPUs because the
kernel already uses Fixed delivery mode for IPIs. The reason for this is
that th SDM explicitely forbids lowest prio mode for IPIs. The reason is
obvious: If the irq routing does not honor destination targets in lowest
prio mode then an IPI targeted at CPU1 might end up on CPU0, which would be
a fatal problem in many cases.

As a consequence of this change, the apic::irq_delivery_mode field is now
pointless, but this needs to be cleaned up in a separate patch.

Fixes: fdba46ff ("x86/apic: Get rid of multi CPU affinity")
Reported-by: vcaputo@pengaru.com
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Tested-by: vcaputo@pengaru.com
Cc: Pavel Machek <pavel@ucw.cz>
Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1712281140440.1688@nanos

There are two consumers of apic=:
  apic_set_verbosity() for setting the APIC debug level;
  parse_apic() for registering APIC driver by hand.

X86-32 supports both of them, but sometimes, kernel issues a weird warning.
eg: when kernel was booted up with 'apic=bigsmp' in command line,
early_param would warn like that:

...
[    0.000000] APIC Verbosity level bigsmp not recognised use apic=verbose or apic=debug
[    0.000000] Malformed early option 'apic'
...

Wrap the warning code in CONFIG_X86_64 case to avoid this.
Signed-off-by: NDou Liyang <douly.fnst@cn.fujitsu.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: peterz@infradead.org
Cc: rdunlap@infradead.org
Cc: corbet@lwn.net
Link: https://lkml.kernel.org/r/20171204040313.24824-1-douly.fnst@cn.fujitsu.com

The IRQ code already has support for lockdep class for the lock mutex
in an interrupt descriptor. Extend this to add a second class for the
request mutex in the descriptor. Not having a class is resulting in
false positive splats in some code paths.
Signed-off-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: linus.walleij@linaro.org
Cc: grygorii.strashko@ti.com
Cc: f.fainelli@gmail.com
Link: https://lkml.kernel.org/r/1512234664-21555-1-git-send-email-andrew@lunn.ch

Commit v4.12-rc4-1-g9289ea7f introduced a mistake that made the
64-bit hweight stub call the 16-bit hweight function.

Fixes: 9289ea7f ("sparc64: Use indirect calls in hamming weight stubs")
Signed-off-by: NJan Engelhardt <jengelh@inai.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit e802a51e ("x86/idt: Consolidate IDT invalidation") cleaned up
and unified the IDT invalidation that existed in a couple of places.  It
changed no actual real code.

Despite not changing any actual real code, it _did_ change code generation:
by implementing the common idt_invalidate() function in
archx86/kernel/idt.c, it made the use of the function in
arch/x86/kernel/machine_kexec_32.c be a real function call rather than an
(accidental) inlining of the function.

That, in turn, exposed two issues:

 - in load_segments(), we had incorrectly reset all the segment
   registers, which then made the stack canary load (which gcc does
   using offset of %gs) cause a trap.  Instead of %gs pointing to the
   stack canary, it will be the normal zero-based kernel segment, and
   the stack canary load will take a page fault at address 0x14.

 - to make this even harder to debug, we had invalidated the GDT just
   before calling idt_invalidate(), which meant that the fault happened
   with an invalid GDT, which in turn causes a triple fault and
   immediate reboot.

Fix this by

 (a) not reloading the special segments in load_segments(). We currently
     don't do any percpu accesses (which would require %fs on x86-32) in
     this area, but there's no reason to think that we might not want to
     do them, and like %gs, it's pointless to break it.

 (b) doing idt_invalidate() before invalidating the GDT, to keep things
     at least _slightly_ more debuggable for a bit longer. Without a
     IDT, traps will not work. Without a GDT, traps also will not work,
     but neither will any segment loads etc. So in a very real sense,
     the GDT is even more core than the IDT.

Fixes: e802a51e ("x86/idt: Consolidate IDT invalidation")
Reported-and-tested-by: NAlexandru Chirvasitu <achirvasub@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/alpine.LFD.2.21.1712271143180.8572@i7.lan