Commit Graph

142 Commits

Author SHA1 Message Date
Mike Rapoport
3f08a302f5 mm: remove CONFIG_HAVE_MEMBLOCK_NODE_MAP option
CONFIG_HAVE_MEMBLOCK_NODE_MAP is used to differentiate initialization of
nodes and zones structures between the systems that have region to node
mapping in memblock and those that don't.

Currently all the NUMA architectures enable this option and for the
non-NUMA systems we can presume that all the memory belongs to node 0 and
therefore the compile time configuration option is not required.

The remaining few architectures that use DISCONTIGMEM without NUMA are
easily updated to use memblock_add_node() instead of memblock_add() and
thus have proper correspondence of memblock regions to NUMA nodes.

Still, free_area_init_node() must have a backward compatible version
because its semantics with and without CONFIG_HAVE_MEMBLOCK_NODE_MAP is
different.  Once all the architectures will use the new semantics, the
entire compatibility layer can be dropped.

To avoid addition of extra run time memory to store node id for
architectures that keep memblock but have only a single node, the node id
field of the memblock_region is guarded by CONFIG_NEED_MULTIPLE_NODES and
the corresponding accessors presume that in those cases it is always 0.

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Hoan Tran <hoan@os.amperecomputing.com>	[arm64]
Acked-by: Catalin Marinas <catalin.marinas@arm.com>	[arm64]
Cc: Baoquan He <bhe@redhat.com>
Cc: Brian Cain <bcain@codeaurora.org>
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: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Simek <monstr@monstr.eu>
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: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200412194859.12663-4-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-03 20:09:43 -07:00
Anshuman Khandual
5093c5872b mm/vma: append unlikely() while testing VMA access permissions
It is unlikely that an inaccessible VMA without required permission flags
will get a page fault.  Hence lets just append unlikely() directive to
such checks in order to improve performance while also standardizing it
across various platforms.

Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Link: http://lkml.kernel.org/r/1582525304-32113-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07 10:43:38 -07:00
Anshuman Khandual
3122e80efc mm/vma: make vma_is_accessible() available for general use
Lets move vma_is_accessible() helper to include/linux/mm.h which makes it
available for general use.  While here, this replaces all remaining open
encodings for VMA access check with vma_is_accessible().

Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Guo Ren <guoren@kernel.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Guo Ren <guoren@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Nick Piggin <npiggin@gmail.com>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/1582520593-30704-3-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07 10:43:37 -07:00
Peter Xu
4064b98270 mm: allow VM_FAULT_RETRY for multiple times
The idea comes from a discussion between Linus and Andrea [1].

Before this patch we only allow a page fault to retry once.  We achieved
this by clearing the FAULT_FLAG_ALLOW_RETRY flag when doing
handle_mm_fault() the second time.  This was majorly used to avoid
unexpected starvation of the system by looping over forever to handle the
page fault on a single page.  However that should hardly happen, and after
all for each code path to return a VM_FAULT_RETRY we'll first wait for a
condition (during which time we should possibly yield the cpu) to happen
before VM_FAULT_RETRY is really returned.

This patch removes the restriction by keeping the FAULT_FLAG_ALLOW_RETRY
flag when we receive VM_FAULT_RETRY.  It means that the page fault handler
now can retry the page fault for multiple times if necessary without the
need to generate another page fault event.  Meanwhile we still keep the
FAULT_FLAG_TRIED flag so page fault handler can still identify whether a
page fault is the first attempt or not.

Then we'll have these combinations of fault flags (only considering
ALLOW_RETRY flag and TRIED flag):

  - ALLOW_RETRY and !TRIED:  this means the page fault allows to
                             retry, and this is the first try

  - ALLOW_RETRY and TRIED:   this means the page fault allows to
                             retry, and this is not the first try

  - !ALLOW_RETRY and !TRIED: this means the page fault does not allow
                             to retry at all

  - !ALLOW_RETRY and TRIED:  this is forbidden and should never be used

In existing code we have multiple places that has taken special care of
the first condition above by checking against (fault_flags &
FAULT_FLAG_ALLOW_RETRY).  This patch introduces a simple helper to detect
the first retry of a page fault by checking against both (fault_flags &
FAULT_FLAG_ALLOW_RETRY) and !(fault_flag & FAULT_FLAG_TRIED) because now
even the 2nd try will have the ALLOW_RETRY set, then use that helper in
all existing special paths.  One example is in __lock_page_or_retry(), now
we'll drop the mmap_sem only in the first attempt of page fault and we'll
keep it in follow up retries, so old locking behavior will be retained.

This will be a nice enhancement for current code [2] at the same time a
supporting material for the future userfaultfd-writeprotect work, since in
that work there will always be an explicit userfault writeprotect retry
for protected pages, and if that cannot resolve the page fault (e.g., when
userfaultfd-writeprotect is used in conjunction with swapped pages) then
we'll possibly need a 3rd retry of the page fault.  It might also benefit
other potential users who will have similar requirement like userfault
write-protection.

GUP code is not touched yet and will be covered in follow up patch.

Please read the thread below for more information.

[1] https://lore.kernel.org/lkml/20171102193644.GB22686@redhat.com/
[2] https://lore.kernel.org/lkml/20181230154648.GB9832@redhat.com/

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Suggested-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Brian Geffon <bgeffon@google.com>
Cc: Bobby Powers <bobbypowers@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Denis Plotnikov <dplotnikov@virtuozzo.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Kirill A . Shutemov" <kirill@shutemov.name>
Cc: Martin Cracauer <cracauer@cons.org>
Cc: Marty McFadden <mcfadden8@llnl.gov>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Maya Gokhale <gokhale2@llnl.gov>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Link: http://lkml.kernel.org/r/20200220160246.9790-1-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:30 -07:00
Peter Xu
dde1607248 mm: introduce FAULT_FLAG_DEFAULT
Although there're tons of arch-specific page fault handlers, most of them
are still sharing the same initial value of the page fault flags.  Say,
merely all of the page fault handlers would allow the fault to be retried,
and they also allow the fault to respond to SIGKILL.

Let's define a default value for the fault flags to replace those initial
page fault flags that were copied over.  With this, it'll be far easier to
introduce new fault flag that can be used by all the architectures instead
of touching all the archs.

Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Brian Geffon <bgeffon@google.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Bobby Powers <bobbypowers@gmail.com>
Cc: Denis Plotnikov <dplotnikov@virtuozzo.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Kirill A . Shutemov" <kirill@shutemov.name>
Cc: Martin Cracauer <cracauer@cons.org>
Cc: Marty McFadden <mcfadden8@llnl.gov>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Maya Gokhale <gokhale2@llnl.gov>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Link: http://lkml.kernel.org/r/20200220160238.9694-1-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:29 -07:00
Peter Xu
4ef873226c mm: introduce fault_signal_pending()
For most architectures, we've got a quick path to detect fatal signal
after a handle_mm_fault().  Introduce a helper for that quick path.

It cleans the current codes a bit so we don't need to duplicate the same
check across archs.  More importantly, this will be an unified place that
we handle the signal immediately right after an interrupted page fault, so
it'll be much easier for us if we want to change the behavior of handling
signals later on for all the archs.

Note that currently only part of the archs are using this new helper,
because some archs have their own way to handle signals.  In the follow up
patches, we'll try to apply this helper to all the rest of archs.

Another note is that the "regs" parameter in the new helper is not used
yet.  It'll be used very soon.  Now we kept it in this patch only to avoid
touching all the archs again in the follow up patches.

[peterx@redhat.com: fix sparse warnings]
  Link: http://lkml.kernel.org/r/20200311145921.GD479302@xz-x1
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Brian Geffon <bgeffon@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Bobby Powers <bobbypowers@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Denis Plotnikov <dplotnikov@virtuozzo.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Kirill A . Shutemov" <kirill@shutemov.name>
Cc: Martin Cracauer <cracauer@cons.org>
Cc: Marty McFadden <mcfadden8@llnl.gov>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Maya Gokhale <gokhale2@llnl.gov>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Link: http://lkml.kernel.org/r/20200220155353.8676-4-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:29 -07:00
Peter Zijlstra
518a6b5824 m68k: mm: Fully initialize the page-table allocator
Also iterate the PMD tables to populate the PTE table allocator. This
also fully replaces the previous zero_pgtable hack.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Greg Ungerer <gerg@linux-m68k.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Tested-by: Greg Ungerer <gerg@linux-m68k.org>
Link: https://lore.kernel.org/r/20200131125403.938797587@infradead.org
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2020-02-10 10:57:48 +01:00
Peter Zijlstra
0e071ee681 m68k: mm: Extend table allocator for multiple sizes
In addition to the PGD/PMD table size (128*4) add a PTE table size
(64*4) to the table allocator. This completely removes the pte-table
overhead compared to the old code, even for dense tables.

Notes:

 - the allocator gained a list_empty() check to deal with there not
   being any pages at all.

 - the free mask is extended to cover more than the 8 bits required
   for the (512 byte) PGD/PMD tables.

 - NR_PAGETABLE accounting is restored.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Greg Ungerer <gerg@linux-m68k.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Tested-by: Greg Ungerer <gerg@linux-m68k.org>
Link: https://lore.kernel.org/r/20200131125403.882175409@infradead.org
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2020-02-10 10:57:48 +01:00
Peter Zijlstra
ef9285f69f m68k: mm: Improve kernel_page_table()
With the PTE-tables now only being 256 bytes, allocating a full page
for them is a giant waste. Start by improving the boot time allocator
such that init_mm initialization will at least have optimal memory
density.

Much thanks to Will Deacon in help with debugging and ferreting out
lost information on these dusty MMUs.

Notes:

 - _TABLE_MASK is reduced to account for the shorter (256 byte)
   alignment of pte-tables, per the manual, table entries should only
   ever have state in the low 4 bits (Used,WrProt,Desc1,Desc0) so it is
   still longer than strictly required. (Thanks Will!!!)

 - Also use kernel_page_table() for the 020/030 zero_pgtable case and
   consequently remove the zero_pgtable init hack (will fix up later).

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Greg Ungerer <gerg@linux-m68k.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Tested-by: Greg Ungerer <gerg@linux-m68k.org>
Link: https://lore.kernel.org/r/20200131125403.768263973@infradead.org
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2020-02-10 10:57:48 +01:00
Peter Zijlstra
ef22d8abd8 m68k: mm: Restructure Motorola MMU page-table layout
The Motorola 68xxx MMUs, 040 (and later) have a fixed 7,7,{5,6}
page-table setup, where the last depends on the page-size selected (8k
vs 4k resp.), and head.S selects 4K pages. For 030 (and earlier) we
explicitly program 7,7,6 and 4K pages in %tc.

However, the current code implements this mightily weird. What it does
is group 16 of those (6 bit) pte tables into one 4k page to not waste
space. The down-side is that that forces pmd_t to be a 16-tuple
pointing to consecutive pte tables.

This breaks the generic code which assumes READ_ONCE(*pmd) will be
word sized.

Therefore implement a straight forward 7,7,6 3 level page-table setup,
with the addition (for 020/030) of (partial) large-page support. For
now this increases the memory footprint for pte-tables 15 fold.

Tested with ARAnyM/68040 emulation.

Suggested-by: Will Deacon <will@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Greg Ungerer <gerg@linux-m68k.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Tested-by: Greg Ungerer <gerg@linux-m68k.org>
Link: https://lore.kernel.org/r/20200131125403.711478295@infradead.org
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2020-02-10 10:57:48 +01:00
Peter Zijlstra
5ad272abee m68k: mm: Move the pointer table allocator to motorola.c
Only the Motorola MMU makes use of this allocator, it is a waste of
.text to include it for Sun3/ColdFire. Also, this is going to avoid
build issues when we're going to make it more Motorola specific.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Greg Ungerer <gerg@linux-m68k.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Tested-by: Greg Ungerer <gerg@linux-m68k.org>
Link: https://lore.kernel.org/r/20200131125403.654652162@infradead.org
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2020-02-10 10:57:48 +01:00
Peter Zijlstra
13076a29d5 m68k: mm: Unify Motorola MMU page setup
Seeing how there are 5 copies of this magic code, one of which is
unexplainably different, unify and document things.

Suggested-by: Will Deacon <will@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Greg Ungerer <gerg@linux-m68k.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Tested-by: Greg Ungerer <gerg@linux-m68k.org>
Link: https://lore.kernel.org/r/20200131125403.597688427@infradead.org
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2020-02-10 10:57:48 +01:00
Mike Rapoport
60e50f34b1 m68k: mm: use pgtable-nopXd instead of 4level-fixup
m68k has two or three levels of page tables and can use appropriate
pgtable-nopXd and folding of the upper layers.

Replace usage of include/asm-generic/4level-fixup.h and explicit
definitions of __PAGETABLE_PxD_FOLDED in m68k with
include/asm-generic/pgtable-nopmd.h for two-level configurations and
with include/asm-generic/pgtable-nopud.h for three-lelve configurations
and adjust page table manipulation macros and functions accordingly.

[akpm@linux-foundation.org: fix merge glitch]
[geert@linux-m68k.org: more merge glitch fixes]
[akpm@linux-foundation.org: s/bad_pgd/bad_pud/, per Mike]
Link: http://lkml.kernel.org/r/1572938135-31886-6-git-send-email-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Greg Ungerer <gerg@linux-m68k.org>
Cc: Anatoly Pugachev <matorola@gmail.com>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Peter Rosin <peda@axentia.se>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Sam Creasey <sammy@sammy.net>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-04 19:44:15 -08:00
Christoph Hellwig
076863473c m68k: rename __iounmap and mark it static
m68k uses __iounmap as the name for an internal helper that is only
used for some CPU types.  Mark it static, give it a better name
and move it around a bit to avoid a forward declaration.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
2019-11-11 21:18:19 +01:00
Eric W. Biederman
2e1661d267 signal: Remove the task parameter from force_sig_fault
As synchronous exceptions really only make sense against the current
task (otherwise how are you synchronous) remove the task parameter
from from force_sig_fault to make it explicit that is what is going
on.

The two known exceptions that deliver a synchronous exception to a
stopped ptraced task have already been changed to
force_sig_fault_to_task.

The callers have been changed with the following emacs regular expression
(with obvious variations on the architectures that take more arguments)
to avoid typos:

force_sig_fault[(]\([^,]+\)[,]\([^,]+\)[,]\([^,]+\)[,]\W+current[)]
->
force_sig_fault(\1,\2,\3)

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2019-05-29 09:31:43 -05:00
Christoph Hellwig
4afd58e14d initramfs: provide a generic free_initrd_mem implementation
For most architectures free_initrd_mem just expands to the same
free_reserved_area call.  Provide that as a generic implementation marked
__weak.

Link: http://lkml.kernel.org/r/20190213174621.29297-8-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>	[m68k]
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>	[arm64]
Cc: Steven Price <steven.price@arm.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 09:47:47 -07:00
Mike Rapoport
8a7f97b902 treewide: add checks for the return value of memblock_alloc*()
Add check for the return value of memblock_alloc*() functions and call
panic() in case of error.  The panic message repeats the one used by
panicing memblock allocators with adjustment of parameters to include
only relevant ones.

The replacement was mostly automated with semantic patches like the one
below with manual massaging of format strings.

  @@
  expression ptr, size, align;
  @@
  ptr = memblock_alloc(size, align);
  + if (!ptr)
  + 	panic("%s: Failed to allocate %lu bytes align=0x%lx\n", __func__, size, align);

[anders.roxell@linaro.org: use '%pa' with 'phys_addr_t' type]
  Link: http://lkml.kernel.org/r/20190131161046.21886-1-anders.roxell@linaro.org
[rppt@linux.ibm.com: fix format strings for panics after memblock_alloc]
  Link: http://lkml.kernel.org/r/1548950940-15145-1-git-send-email-rppt@linux.ibm.com
[rppt@linux.ibm.com: don't panic if the allocation in sparse_buffer_init fails]
  Link: http://lkml.kernel.org/r/20190131074018.GD28876@rapoport-lnx
[akpm@linux-foundation.org: fix xtensa printk warning]
Link: http://lkml.kernel.org/r/1548057848-15136-20-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Reviewed-by: Guo Ren <ren_guo@c-sky.com>		[c-sky]
Acked-by: Paul Burton <paul.burton@mips.com>		[MIPS]
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>	[s390]
Reviewed-by: Juergen Gross <jgross@suse.com>		[Xen]
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>	[m68k]
Acked-by: Max Filippov <jcmvbkbc@gmail.com>		[xtensa]
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Christoph Hellwig <hch@lst.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-12 10:04:02 -07:00
Mike Rapoport
0240dfd5b4 arch: don't memset(0) memory returned by memblock_alloc()
memblock_alloc() already clears the allocated memory, no point in doing
it twice.

Link: http://lkml.kernel.org/r/1548057848-15136-14-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>	[m68k]
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Christoph Hellwig <hch@lst.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Guo Ren <ren_guo@c-sky.com>				[c-sky]
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Juergen Gross <jgross@suse.com>			[Xen]
Cc: Mark Salter <msalter@redhat.com>
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: Paul Burton <paul.burton@mips.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-12 10:04:01 -07:00
David Hildenbrand
5ffb90b393 m68k/mm: use __ClearPageReserved()
The PG_reserved flag is cleared from memory that is part of the kernel
image (and therefore marked as PG_reserved).  Avoid using PG_reserved
directly.

Link: http://lkml.kernel.org/r/20190114125903.24845-6-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-05 21:07:18 -08:00
Linus Torvalds
1d51b4b1d3 m68k fixes for 4.20
- Fix memblock-related crashes.
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Merge tag 'm68k-for-v4.20-tag2' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k

Pull m68k fix from Geert Uytterhoeven:
 "Fix memblock-related crashes"

* tag 'm68k-for-v4.20-tag2' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k:
  m68k: Fix memblock-related crashes
2018-12-20 07:35:16 -08:00
Geert Uytterhoeven
bed1369f51 m68k: Fix memblock-related crashes
When running the kernel in Fast RAM on Atari:

    Ignoring memory chunk at 0x0:0xe00000 before the first chunk
    ...
    Unable to handle kernel NULL pointer dereference at virtual address (ptrval)
    Oops: 00000000
    Modules linked in:
    PC: [<0069dbac>] free_all_bootmem+0x12c/0x186
    SR: 2714  SP: (ptrval)  a2: 005e3314
    d0: 00000000    d1: 0000000a    d2: 00000e00    d3: 00000000
    d4: 005e1fc0    d5: 0000001a    a0: 01000000    a1: 00000000
    Process swapper (pid: 0, task=(ptrval))
    Frame format=7 eff addr=00000736 ssw=0505 faddr=00000736
    wb 1 stat/addr/data: 0000 00000000 00000000
    wb 2 stat/addr/data: 0000 00000000 00000000
    wb 3 stat/addr/data: 0000 00000736 00000000
    push data: 00000000 00000000 00000000 00000000
    Stack from 005e1f84:
            00000000 0000000a 027d3260 006b5006 00000000 00000000 00000000 00000000
            0004f062 0003a220 0069e272 005e1ff8 0000054c 00000000 00e00000 00000000
            00000001 00693cd8 027d3260 0004f062 0003a220 00691be6 00000000 00000000
            00000000 00000000 00000000 00000000 006b5006 00000000 00690872
    Call Trace: [<0004f062>] printk+0x0/0x18
     [<0003a220>] parse_args+0x0/0x2d4
     [<0069e272>] memblock_virt_alloc_try_nid+0x0/0xa4
     [<00693cd8>] mem_init+0xa/0x5c
     [<0004f062>] printk+0x0/0x18
     [<0003a220>] parse_args+0x0/0x2d4
     [<00691be6>] start_kernel+0x1ca/0x462
     [<00690872>] _sinittext+0x872/0x11f8
    Code: 7a1a eaae 2270 6db0 0061 ef14 2f01 2f03 <96a9> 0736 2203 e589 d681 e78b d6a9 0732 2f03 2f40 0034 4eb9 0069 b8d0 260e 4fef
    Disabling lock debugging due to kernel taint
    Kernel panic - not syncing: Attempted to kill the idle task!

As the kernel must run in the memory chunk with the lowest address,
ST-RAM is ignored, and removed from the m68k_memory[] array.
However, it is not removed from memblock, causing a crash later.

More investigation shows that there are 3 places where memory chunks are
ignored, all after the calls to memblock_add() in m68k_parse_bootinfo(),
and thus causing crashes:
  1. On classic m68k CPUs with a MMU, paging_init() ignores all memory
     chunks below the first chunk, cfr. above,
  2. On Amigas equipped with a Zorro III bus, config_amiga() ignores all
     Zorro II memory,
  3. If CONFIG_SINGLE_MEMORY_CHUNK=y, m68k_parse_bootinfo() ignores all
     but the first memory chunk.

Fix this by moving the calls to memblock_add() from
m68k_parse_bootinfo() to paging_init(), after all ignored memory chunks
have been removed from m68k_memory[].

Reported-by: Andreas Schwab <schwab@linux-m68k.org>
Fixes: 1008a11590 ("m68k: switch to MEMBLOCK + NO_BOOTMEM")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2018-12-19 17:24:12 +01:00
Mike Rapoport
57c8a661d9 mm: remove include/linux/bootmem.h
Move remaining definitions and declarations from include/linux/bootmem.h
into include/linux/memblock.h and remove the redundant header.

The includes were replaced with the semantic patch below and then
semi-automated removal of duplicated '#include <linux/memblock.h>

@@
@@
- #include <linux/bootmem.h>
+ #include <linux/memblock.h>

[sfr@canb.auug.org.au: dma-direct: fix up for the removal of linux/bootmem.h]
  Link: http://lkml.kernel.org/r/20181002185342.133d1680@canb.auug.org.au
[sfr@canb.auug.org.au: powerpc: fix up for removal of linux/bootmem.h]
  Link: http://lkml.kernel.org/r/20181005161406.73ef8727@canb.auug.org.au
[sfr@canb.auug.org.au: x86/kaslr, ACPI/NUMA: fix for linux/bootmem.h removal]
  Link: http://lkml.kernel.org/r/20181008190341.5e396491@canb.auug.org.au
Link: http://lkml.kernel.org/r/1536927045-23536-30-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Michal Hocko <mhocko@suse.com>
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 Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Serge Semin <fancer.lancer@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-31 08:54:16 -07:00
Mike Rapoport
c6ffc5ca8f memblock: rename free_all_bootmem to memblock_free_all
The conversion is done using

sed -i 's@free_all_bootmem@memblock_free_all@' \
    $(git grep -l free_all_bootmem)

Link: http://lkml.kernel.org/r/1536927045-23536-26-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
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 Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Serge Semin <fancer.lancer@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-31 08:54:16 -07:00
Mike Rapoport
15c3c114ed memblock: replace alloc_bootmem_pages with memblock_alloc
The alloc_bootmem_pages() function allocates PAGE_SIZE aligned memory.
memblock_alloc() with alignment set to PAGE_SIZE does exactly the same
thing.

The conversion is done using the following semantic patch:

@@
expression e;
@@
- alloc_bootmem_pages(e)
+ memblock_alloc(e, PAGE_SIZE)

Link: http://lkml.kernel.org/r/1536927045-23536-20-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
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 Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Serge Semin <fancer.lancer@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-31 08:54:15 -07:00
Mike Rapoport
e8625dce71 memblock: replace alloc_bootmem_low_pages with memblock_alloc_low
The alloc_bootmem_low_pages() function allocates PAGE_SIZE aligned regions
from low memory. memblock_alloc_low() with alignment set to PAGE_SIZE does
exactly the same thing.

The conversion is done using the following semantic patch:

@@
expression e;
@@
- alloc_bootmem_low_pages(e)
+ memblock_alloc_low(e, PAGE_SIZE)

Link: http://lkml.kernel.org/r/1536927045-23536-19-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
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 Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Serge Semin <fancer.lancer@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-31 08:54:15 -07:00
Mike Rapoport
c90bbce9ee m68k: fix early memory reservation for ColdFire MMU systems
The bootmem to memblock conversion introduced by the commit 1008a11590
("m68k: switch to MEMBLOCK + NO_BOOTMEM") made reservation of kernel code
and data to start from a wrong address.

Fix it.

Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Tested-by: Angelo Dureghello <angelo@sysam.it>
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
2018-09-03 10:19:36 +10:00
Souptick Joarder
50a7ca3c6f mm: convert return type of handle_mm_fault() caller to vm_fault_t
Use new return type vm_fault_t for fault handler.  For now, this is just
documenting that the function returns a VM_FAULT value rather than an
errno.  Once all instances are converted, vm_fault_t will become a
distinct type.

Ref-> commit 1c8f422059 ("mm: change return type to vm_fault_t")

In this patch all the caller of handle_mm_fault() are changed to return
vm_fault_t type.

Link: http://lkml.kernel.org/r/20180617084810.GA6730@jordon-HP-15-Notebook-PC
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: James Hogan <jhogan@kernel.org>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: David S. Miller <davem@davemloft.net>
Cc: Richard Weinberger <richard@nod.at>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Levin, Alexander (Sasha Levin)" <alexander.levin@verizon.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-17 16:20:28 -07:00
Mike Rapoport
1008a11590 m68k: switch to MEMBLOCK + NO_BOOTMEM
In m68k the physical memory is described by [memory_start, memory_end] for
!MMU variant and by m68k_memory array of memory ranges for the MMU version.
This information is directly use to register the physical memory with
memblock.

The reserve_bootmem() calls are replaced with memblock_reserve() and the
bootmap bitmap allocation is simply dropped.

Since the MMU variant creates early mappings only for the small part of the
memory we force bottom-up allocations in memblock.

Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Acked-by: Greg Ungerer <gerg@linux-m68k.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2018-07-29 10:48:18 +02:00
Linus Torvalds
eab733afcb Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu
Pull m68knommu updates from Greg Ungerer:
 "These changes all relate to converting the IO access functions for the
  ColdFire (and all other non-MMU m68k) platforms to use asm-generic IO
  instead.

  This makes the IO support the same on all ColdFire (regardless of MMU
  enabled or not) and means we can now support PCI in non-MMU mode.

  As a bonus these changes remove more code than they add"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
  m68k: fix ColdFire PCI config reads and writes
  m68k: introduce iomem() macro for __iomem conversions
  m68k: allow ColdFire PCI bus on MMU and non-MMU configuration
  m68k: fix ioremapping for internal ColdFire peripherals
  m68k: fix read/write multi-byte IO for PCI on ColdFire
  m68k: don't redefine access functions if we have PCI
  m68k: remove old ColdFire IO access support code
  m68k: use io_no.h for MMU and non-MMU enabled ColdFire
  m68k: setup PCI support code in io_no.h
  m68k: group io mapping definitions and functions
  m68k: rework raw access macros for the non-MMU case
  m68k: use asm-generic/io.h for non-MMU io access functions
  m68k: put definition guards around virt_to_phys and phys_to_virt
  m68k: move *_relaxed macros into io_no.h and io_mm.h
2018-06-05 10:51:30 -07:00
Linus Torvalds
137f5ae4da m68k updates for 4.18
- A few time-related fixes:
       - off-by-one calendar month on some classes of machines,
       - Y2038 preparation,
   - Build fix for ndelay() being called with a 64-bit type,
   - Revive 64-bit get_user(), which is used by some Android code,
   - Defconfig updates,
   - Fix for a long-standing fatal bug in iounmap() on '020/030, which
     was actually fixed in 2.4.23, but never in 2.5.x and later,
   - Default DMA mask to avoid warning splats,
   - Minor fixes and cleanups.
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Merge tag 'm68k-for-v4.18-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k

Pull m68k updates from Geert Uytterhoeven:

 - a few time-related fixes:
     - off-by-one calendar month on some classes of machines
     - Y2038 preparation

 - build fix for ndelay() being called with a 64-bit type

 - revive 64-bit get_user(), which is used by some Android code

 - defconfig updates

 - fix for a long-standing fatal bug in iounmap() on '020/030, which was
   actually fixed in 2.4.23, but never in 2.5.x and later

 - default DMA mask to avoid warning splats

 - minor fixes and cleanups

* tag 'm68k-for-v4.18-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k:
  m68k: Set default dma mask for platform devices
  m68k/mm: Adjust VM area to be unmapped by gap size for __iounmap()
  m68k/defconfig: Update defconfigs for v4.17-rc3
  m68k/uaccess: Revive 64-bit get_user()
  m68k: Implement ndelay() as an inline function to force type checking/casting
  zorro: Add a blank line after declarations
  m68k: Use read_persistent_clock64() consistently
  m68k: Fix off-by-one calendar month
  m68k: Fix style, spelling, and grammar in siginfo_build_tests()
  m68k/mac: Fix SWIM memory resource end address
2018-06-04 15:50:22 -07:00
Greg Ungerer
be39cbcbd6 m68k: fix ioremapping for internal ColdFire peripherals
The ColdFire SoC internal peripherals are mapped into virtual address
space using the ACR registers of the cache control unit. This means we
are using a 1:1 physical:virtual mapping for them that does not rely on
page table mappings. We can quickly determine if we are accessing an
internal peripheral device given the physical or vitrual address using
the same range check.

The implications of this mapping is that an ioremap should return the
physical address as the virtual mapping __iomem cookie as well. So fix
ioremap() to deal with this on ColdFire. Of course you need to take
care of this in the iounmap() path as well.

Reported-by: Angelo Dureghello <angelo@sysam.it>
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
Reviewed-by: Angelo Dureghello <angelo@sysam.it>
Tested-by: Angelo Dureghello <angelo@sysam.it>
2018-05-28 09:45:27 +10:00
Michael Schmitz
3f90f9ef2d m68k/mm: Adjust VM area to be unmapped by gap size for __iounmap()
If 020/030 support is enabled, get_io_area() leaves an IO_SIZE gap
between mappings which is added to the vm_struct representing the
mapping.  __ioremap() uses the actual requested size (after alignment),
while __iounmap() is passed the size from the vm_struct.

On 020/030, early termination descriptors are used to set up mappings of
extent 'size', which are validated on unmapping. The unmapped gap of
size IO_SIZE defeats the sanity check of the pmd tables, causing
__iounmap() to loop forever on 030.

On 040/060, unmapping of page table entries does not check for a valid
mapping, so the umapping loop always completes there.

Adjust size to be unmapped by the gap that had been added in the
vm_struct prior.

This fixes the hang in atari_platform_init() reported a long time ago,
and a similar one reported by Finn recently (addressed by removing
ioremap() use from the SWIM driver.

Tested on my Falcon in 030 mode - untested but should work the same on
040/060 (the extra page tables cleared there would never have been set
up anyway).

Signed-off-by: Michael Schmitz <schmitzmic@gmail.com>
[geert: Minor commit description improvements]
[geert: This was fixed in 2.4.23, but not in 2.5.x]
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: stable@vger.kernel.org
2018-05-24 12:00:27 +02:00
Eric W. Biederman
3c67075d5d signal/m68k: Use force_sig_fault where appropriate
Filling in struct siginfo before calling force_sig_info a tedious and
error prone process, where once in a great while the wrong fields
are filled out, and siginfo has been inconsistently cleared.

Simplify this process by using the helper force_sig_fault.  Which
takes as a parameters all of the information it needs, ensures
all of the fiddly bits of filling in struct siginfo are done properly
and then calls force_sig_info.

In short about a 5 line reduction in code for every time force_sig_info
is called, which makes the calling function clearer.

Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: linux-m68k@lists.linux-m68k.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-04-25 10:41:01 -05:00
Geert Uytterhoeven
31833332f7 m68k/mm: Stop printing the virtual memory layout
Since commit ad67b74d24 ("printk: hash addresses printed with
%p"), the virtual memory layout printed during boot up contains "ptrval"
instead of actual addresses:

    Memory: 268040K/276480K available (2979K kernel code, 310K rwdata, 784K rodata, 144K init, 172K bss, 8440K reserved, 0K cma-reserved)
    Virtual kernel memory layout:
	vector  : 0x003d2e74 - 0x003d3274   (   1 KiB)
	kmap    : 0xd0000000 - 0xf0000000   ( 512 MiB)
	vmalloc : 0x11800000 - 0xd0000000   (3048 MiB)
	lowmem  : 0x00000000 - 0x11000000   ( 272 MiB)
	  .init : 0x(ptrval) - 0x(ptrval)   ( 144 KiB)
	  .text : 0x(ptrval) - 0x(ptrval)   (2980 KiB)
	  .data : 0x(ptrval) - 0x(ptrval)   (1095 KiB)
	  .bss  : 0x(ptrval) - 0x(ptrval)   ( 173 KiB)

Instead of changing the printing to "%px", and leaking virtual memory
layout information again, just remove the printing completely, cfr. e.g.
commit 071929dbdd ("arm64: Stop printing the virtual memory
layout").

All interesting information (actual section sizes) is already printed by
mem_init_print_info() just above anyway.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2018-03-19 10:22:59 +01:00
Eric W. Biederman
5f74972ce6 signal: Don't use structure initializers for struct siginfo
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: "Eric W. Biederman" <ebiederm@xmission.com>
2018-01-22 19:07:08 -06:00
Greg Ungerer
f55ab8f275 m68k: fix ColdFire node shift size calculation
The m68k pg_data_table is a fix size array defined in arch/m68k/mm/init.c.
Index numbers within it are defined based on memory size. But for Coldfire
these don't take into account a non-zero physical RAM base address, and this
causes us to access past the end of this array at system start time.

Change the node shift calculation so that we keep the index inside its range.

Reported-by: Angelo Dureghello <angelo@sysam.it>
Tested-by: Angelo Dureghello <angelo@sysam.it>
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
2017-11-06 08:25:20 +10:00
Greg Ungerer
34fa9b2177 m68k: move coldfire MMU initialization code
The M54[78]x ColdFire parts are not the only members of the ColdFire family
that have an MMU. But currently some of the early MMU initialization code
is inside the startup code specific to only the ColdFire M54[78]x parts.
Move that early ColdFire MMU init code so that it is run for other ColdFire
parts running with MMU enabled.

Specifically this means that the MMU initialization code will now also be
run for the ColdFire M5441x parts when running with MMU enabled.

The code move meant that the extern definition for the mmu_context_init()
function had to be moved as well. To make it clear that is ColdFire specific
I have renamed that with a "cf_" in front of it and put its extern definition
in the mcfmmu.h (which is already included by the setup code).

Reported-by: Angelo Dureghello <angelo@sysam.it>
Tested-by: Angelo Dureghello <angelo@sysam.it>
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
2017-11-06 08:25:20 +10:00
Greg Kroah-Hartman
b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Al Viro
68acfdcb47 m68k: switch to generic extable.h
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-03-28 18:23:40 -04:00
Mathias Krause
3dfe33020c m68k/sun3: Remove dead code in paging_init()
The macro TEST_VERIFY_AREA can never be defined as there's no
wp_works_ok variable. So just remove the dead code.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2017-02-13 10:03:19 +01:00
Geert Uytterhoeven
e6991137a3 m68k/mm: Modernize printing of kernel messages
Convert from printk() to pr_*().

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2017-02-12 10:36:53 +01:00
Geert Uytterhoeven
05b70ff69c m68k/mm: sun3 - Modernize printing of kernel messages
- Convert from printk() to pr_*(),
  - Add missing print to do_page_mapin(), as print_pte_vaddr() calls
    pr_cont().

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2017-02-12 10:36:53 +01:00
Linus Torvalds
7c0f6ba682 Replace <asm/uaccess.h> with <linux/uaccess.h> globally
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-24 11:46:01 -08:00
Greg Ungerer
f71160655d m68k: move ColdFire _bootmem_alloc code
The early ColdFire bootmem_alloc() code is currently only included in
the board support for the Coldire 54xx platforms. It will be used on all
ColdFire MMU enabled platforms as others are supported. So move the
mcf54xx_bootmem_alloc() function to be generally available to all MMU
enabled ColdFire parts (and use a more generic name for it).

Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
2016-09-26 12:02:58 +10:00
Kirill A. Shutemov
dcddffd41d mm: do not pass mm_struct into handle_mm_fault
We always have vma->vm_mm around.

Link: http://lkml.kernel.org/r/1466021202-61880-8-git-send-email-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26 16:19:19 -07:00
Geert Uytterhoeven
79ae4fa5c0 m68k/mm: motorola - Add missing initialization of max_pfn
If max_pfn is not initialized, the various /proc/kpage* files are empty,
and selftests/vm/mlock2-tests will fail. max_pfn is also used by the
block layer to calculate DMA masks.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Greg Ungerer <gerg@uclinux.org>
2015-11-22 11:35:24 +01:00
David Hildenbrand
70ffdb9393 mm/fault, arch: Use pagefault_disable() to check for disabled pagefaults in the handler
Introduce faulthandler_disabled() and use it to check for irq context and
disabled pagefaults (via pagefault_disable()) in the pagefault handlers.

Please note that we keep the in_atomic() checks in place - to detect
whether in irq context (in which case preemption is always properly
disabled).

In contrast, preempt_disable() should never be used to disable pagefaults.
With !CONFIG_PREEMPT_COUNT, preempt_disable() doesn't modify the preempt
counter, and therefore the result of in_atomic() differs.
We validate that condition by using might_fault() checks when calling
might_sleep().

Therefore, add a comment to faulthandler_disabled(), describing why this
is needed.

faulthandler_disabled() and pagefault_disable() are defined in
linux/uaccess.h, so let's properly add that include to all relevant files.

This patch is based on a patch from Thomas Gleixner.

Reviewed-and-tested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: David.Laight@ACULAB.COM
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: airlied@linux.ie
Cc: akpm@linux-foundation.org
Cc: benh@kernel.crashing.org
Cc: bigeasy@linutronix.de
Cc: borntraeger@de.ibm.com
Cc: daniel.vetter@intel.com
Cc: heiko.carstens@de.ibm.com
Cc: herbert@gondor.apana.org.au
Cc: hocko@suse.cz
Cc: hughd@google.com
Cc: mst@redhat.com
Cc: paulus@samba.org
Cc: ralf@linux-mips.org
Cc: schwidefsky@de.ibm.com
Cc: yang.shi@windriver.com
Link: http://lkml.kernel.org/r/1431359540-32227-7-git-send-email-dahi@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 08:39:15 +02:00
Linus Torvalds
33692f2759 vm: add VM_FAULT_SIGSEGV handling support
The core VM already knows about VM_FAULT_SIGBUS, but cannot return a
"you should SIGSEGV" error, because the SIGSEGV case was generally
handled by the caller - usually the architecture fault handler.

That results in lots of duplication - all the architecture fault
handlers end up doing very similar "look up vma, check permissions, do
retries etc" - but it generally works.  However, there are cases where
the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV.

In particular, when accessing the stack guard page, libsigsegv expects a
SIGSEGV.  And it usually got one, because the stack growth is handled by
that duplicated architecture fault handler.

However, when the generic VM layer started propagating the error return
from the stack expansion in commit fee7e49d45 ("mm: propagate error
from stack expansion even for guard page"), that now exposed the
existing VM_FAULT_SIGBUS result to user space.  And user space really
expected SIGSEGV, not SIGBUS.

To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those
duplicate architecture fault handlers about it.  They all already have
the code to handle SIGSEGV, so it's about just tying that new return
value to the existing code, but it's all a bit annoying.

This is the mindless minimal patch to do this.  A more extensive patch
would be to try to gather up the mostly shared fault handling logic into
one generic helper routine, and long-term we really should do that
cleanup.

Just from this patch, you can generally see that most architectures just
copied (directly or indirectly) the old x86 way of doing things, but in
the meantime that original x86 model has been improved to hold the VM
semaphore for shorter times etc and to handle VM_FAULT_RETRY and other
"newer" things, so it would be a good idea to bring all those
improvements to the generic case and teach other architectures about
them too.

Reported-and-tested-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Jan Engelhardt <jengelh@inai.de>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # "s390 still compiles and boots"
Cc: linux-arch@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-01-29 10:51:32 -08:00
Himangi Saraogi
f0b99a643e m68k/mm: Eliminate memset after alloc_bootmem_pages
alloc_bootmem and related functions always return a zeroed region of memory.
Thus a memset after calls to these functions is unnecessary.

The following Coccinelle semantic patch was used for making the change:

@@
expression E,E1;
@@

E = \(alloc_bootmem\|alloc_bootmem_low\|alloc_bootmem_pages\|alloc_bootmem_low_pages\)(...)
... when != E
- memset(E,0,E1);

Signed-off-by: Himangi Saraogi <himangi774@gmail.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2014-11-10 09:56:44 +01:00
Geert Uytterhoeven
24cae7934c m68k: Reformat arch/m68k/mm/hwtest.c
No functional changes

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2014-10-03 10:50:56 +02:00