arch: make execmem setup available regardless of CONFIG_MODULES

execmem does not depend on modules, on the contrary modules use
execmem.

To make execmem available when CONFIG_MODULES=n, for instanc

arch: make execmem setup available regardless of CONFIG_MODULES

execmem does not depend on modules, on the contrary modules use
execmem.

To make execmem available when CONFIG_MODULES=n, for instance for
kprobes, split execmem_params initialization out from
arch/*/kernel/module.c and compile it when CONFIG_EXECMEM=y

Signed-off-by: Mike Rapoport (IBM) <[email protected]>
Reviewed-by: Philippe Mathieu-Daudé <[email protected]>
Signed-off-by: Luis Chamberlain <[email protected]>

show more ...

mm/execmem, arch: convert simple overrides of module_alloc to execmem

Several architectures override module_alloc() only to define address
range for code allocations different than VMALLOC address s

mm/execmem, arch: convert simple overrides of module_alloc to execmem

Several architectures override module_alloc() only to define address
range for code allocations different than VMALLOC address space.

Provide a generic implementation in execmem that uses the parameters for
address space ranges, required alignment and page protections provided
by architectures.

The architectures must fill execmem_info structure and implement
execmem_arch_setup() that returns a pointer to that structure. This way the
execmem initialization won't be called from every architecture, but rather
from a central place, namely a core_initcall() in execmem.

The execmem provides execmem_alloc() API that wraps __vmalloc_node_range()
with the parameters defined by the architectures. If an architecture does
not implement execmem_arch_setup(), execmem_alloc() will fall back to
module_alloc().

Signed-off-by: Mike Rapoport (IBM) <[email protected]>
Acked-by: Song Liu <[email protected]>
Reviewed-by: Masami Hiramatsu (Google) <[email protected]>
Signed-off-by: Luis Chamberlain <[email protected]>

show more ...

parisc: module: Mark symindex __maybe_unused

Signed-off-by: Helge Deller <[email protected]>

module: replace module_layout with module_memory

module_layout manages different types of memory (text, data, rodata, etc.)
in one allocation, which is problematic for some reasons:

1. It is hard t

module: replace module_layout with module_memory

module_layout manages different types of memory (text, data, rodata, etc.)
in one allocation, which is problematic for some reasons:

1. It is hard to enable CONFIG_STRICT_MODULE_RWX.
2. It is hard to use huge pages in modules (and not break strict rwx).
3. Many archs uses module_layout for arch-specific data, but it is not
obvious how these data are used (are they RO, RX, or RW?)

Improve the scenario by replacing 2 (or 3) module_layout per module with
up to 7 module_memory per module:

MOD_TEXT,
MOD_DATA,
MOD_RODATA,
MOD_RO_AFTER_INIT,
MOD_INIT_TEXT,
MOD_INIT_DATA,
MOD_INIT_RODATA,

and allocating them separately. This adds slightly more entries to
mod_tree (from up to 3 entries per module, to up to 7 entries per
module). However, this at most adds a small constant overhead to
__module_address(), which is expected to be fast.

Various archs use module_layout for different data. These data are put
into different module_memory based on their location in module_layout.
IOW, data that used to go with text is allocated with MOD_MEM_TYPE_TEXT;
data that used to go with data is allocated with MOD_MEM_TYPE_DATA, etc.

module_memory simplifies quite some of the module code. For example,
ARCH_WANTS_MODULES_DATA_IN_VMALLOC is a lot cleaner, as it just uses a
different allocator for the data. kernel/module/strict_rwx.c is also
much cleaner with module_memory.

Signed-off-by: Song Liu <[email protected]>
Cc: Luis Chamberlain <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Guenter Roeck <[email protected]>
Cc: Christophe Leroy <[email protected]>
Reviewed-by: Thomas Gleixner <[email protected]>
Reviewed-by: Christophe Leroy <[email protected]>
Reviewed-by: Luis Chamberlain <[email protected]>
Signed-off-by: Luis Chamberlain <[email protected]>

show more ...

mm: don't include asm/pgtable.h if linux/mm.h is already included

Patch series "mm: consolidate definitions of page table accessors", v2.

The low level page table accessors (pXY_index(), pXY_offset

mm: don't include asm/pgtable.h if linux/mm.h is already included

Patch series "mm: consolidate definitions of page table accessors", v2.

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

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

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

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

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

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

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

This patch (of 12):

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

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

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

Signed-off-by: Mike Rapoport <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Brian Cain <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Chris Zankel <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Greentime Hu <[email protected]>
Cc: Greg Ungerer <[email protected]>
Cc: Guan Xuetao <[email protected]>
Cc: Guo Ren <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Helge Deller <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Ley Foon Tan <[email protected]>
Cc: Mark Salter <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Matt Turner <[email protected]>
Cc: Max Filippov <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Michal Simek <[email protected]>
Cc: Mike Rapoport <[email protected]>
Cc: Nick Hu <[email protected]>
Cc: Paul Walmsley <[email protected]>
Cc: Richard Weinberger <[email protected]>
Cc: Rich Felker <[email protected]>
Cc: Russell King <[email protected]>
Cc: Stafford Horne <[email protected]>
Cc: Thomas Bogendoerfer <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Tony Luck <[email protected]>
Cc: Vincent Chen <[email protected]>
Cc: Vineet Gupta <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Yoshinori Sato <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

parisc: module: Update references to parisc website

The PA-RISC Linux project web page is now hosted at
https://parisc.wiki.kernel.org

Signed-off-by: Helge Deller <[email protected]>

module/ftrace: handle patchable-function-entry

When using patchable-function-entry, the compiler will record the
callsites into a section named "__patchable_function_entries" rather
than "__mcount_l

module/ftrace: handle patchable-function-entry

When using patchable-function-entry, the compiler will record the
callsites into a section named "__patchable_function_entries" rather
than "__mcount_loc". Let's abstract this difference behind a new
FTRACE_CALLSITE_SECTION, so that architectures don't have to handle this
explicitly (e.g. with custom module linker scripts).

As parisc currently handles this explicitly, it is fixed up accordingly,
with its custom linker script removed. Since FTRACE_CALLSITE_SECTION is
only defined when DYNAMIC_FTRACE is selected, the parisc module loading
code is updated to only use the definition in that case. When
DYNAMIC_FTRACE is not selected, modules shouldn't have this section, so
this removes some redundant work in that case.

To make sure that this is keep up-to-date for modules and the main
kernel, a comment is added to vmlinux.lds.h, with the existing ifdeffery
simplified for legibility.

I built parisc generic-{32,64}bit_defconfig with DYNAMIC_FTRACE enabled,
and verified that the section made it into the .ko files for modules.

Signed-off-by: Mark Rutland <[email protected]>
Acked-by: Helge Deller <[email protected]>
Acked-by: Steven Rostedt (VMware) <[email protected]>
Reviewed-by: Ard Biesheuvel <[email protected]>
Reviewed-by: Torsten Duwe <[email protected]>
Tested-by: Amit Daniel Kachhap <[email protected]>
Tested-by: Sven Schnelle <[email protected]>
Tested-by: Torsten Duwe <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: James E.J. Bottomley <[email protected]>
Cc: Jessica Yu <[email protected]>
Cc: [email protected]

show more ...

parisc: Fix module loading error with JUMP_LABEL feature

Commit 62217beb394e ("parisc: Add static branch and JUMP_LABEL feature") missed
to add code to handle PCREL64 relocations which are generated

parisc: Fix module loading error with JUMP_LABEL feature

Commit 62217beb394e ("parisc: Add static branch and JUMP_LABEL feature") missed
to add code to handle PCREL64 relocations which are generated when creating a
jump label on a 64-bit kernel.

This patch fixes module load errors like this one:
# modprobe -v ipv6
insmod /lib/modules/5.2.0-rc1-JeR/kernel/net/ipv6/ipv6.ko
modprobe: ERROR: could not insert 'ipv6': Exec format error
dmesg reports:
module ipv6: Unknown relocation: 72

Reported-by: Jeroen Roovers <[email protected]>
Tested-by: Jeroen Roovers <[email protected]>
Fixes: 62217beb394e ("parisc: Add static branch and JUMP_LABEL feature")
Signed-off-by: Helge Deller <[email protected]>

show more ...

parisc: add dynamic ftrace

This patch implements dynamic ftrace for PA-RISC. The required mcount
call sequences can get pretty long, so instead of patching the
whole call sequence out of the functio

parisc: add dynamic ftrace

This patch implements dynamic ftrace for PA-RISC. The required mcount
call sequences can get pretty long, so instead of patching the
whole call sequence out of the functions, we are using
-fpatchable-function-entry from gcc. This puts a configurable amount of
NOPS before/at the start of the function. Taking do_sys_open() as example,
which would look like this when the call is patched out:

1036b248: 08 00 02 40 nop
1036b24c: 08 00 02 40 nop
1036b250: 08 00 02 40 nop
1036b254: 08 00 02 40 nop

1036b258 <do_sys_open>:
1036b258: 08 00 02 40 nop
1036b25c: 08 03 02 41 copy r3,r1
1036b260: 6b c2 3f d9 stw rp,-14(sp)
1036b264: 08 1e 02 43 copy sp,r3
1036b268: 6f c1 01 00 stw,ma r1,80(sp)

When ftrace gets enabled for this function the kernel will patch these
NOPs to:

1036b248: 10 19 57 20 <address of ftrace>
1036b24c: 6f c1 00 80 stw,ma r1,40(sp)
1036b250: 48 21 3f d1 ldw -18(r1),r1
1036b254: e8 20 c0 02 bv,n r0(r1)

1036b258 <do_sys_open>:
1036b258: e8 3f 1f df b,l,n .-c,r1
1036b25c: 08 03 02 41 copy r3,r1
1036b260: 6b c2 3f d9 stw rp,-14(sp)
1036b264: 08 1e 02 43 copy sp,r3
1036b268: 6f c1 01 00 stw,ma r1,80(sp)

So the first NOP in do_sys_open() will be patched to jump backwards into
some minimal trampoline code which pushes a stackframe, saves r1 which
holds the return address, loads the address of the real ftrace function,
and branches to that location. For 64 Bit things are getting a bit more
complicated (and longer) because we must make sure that the address of
ftrace location is 8 byte aligned, and the offset passed to ldd for
fetching the address is 8 byte aligned as well.

Note that gcc has a bug which misplaces the function label, and needs a
patch to make dynamic ftrace work. See
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90751 for details.

Signed-off-by: Sven Schnelle <[email protected]>
Signed-off-by: Helge Deller <[email protected]>

show more ...

parisc: use pr_debug() in kernel/module.c

Instead of using our own version, switch to the generic
pr_() calls.

Signed-off-by: Sven Schnelle <[email protected]>
Signed-off-by: Helge Deller <delle

parisc: use pr_debug() in kernel/module.c

Instead of using our own version, switch to the generic
pr_() calls.

Signed-off-by: Sven Schnelle <[email protected]>
Signed-off-by: Helge Deller <[email protected]>

show more ...

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of th

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details you
should have received a copy of the gnu general public license along
with this program if not write to the free software foundation inc
59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Allison Randal <[email protected]>
Reviewed-by: Richard Fontana <[email protected]>
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

parisc: Split out alternative live patching code

Move the alternative implemenation coding to alternative.c and add code to
patch modules while loading.

Signed-off-by: Helge Deller <[email protected]>

parisc64: Add .opd based function descriptor dereference

We are moving towards separate kernel and module function descriptor
dereference callbacks. This patch enables it for parisc64.

For pointers

parisc64: Add .opd based function descriptor dereference

We are moving towards separate kernel and module function descriptor
dereference callbacks. This patch enables it for parisc64.

For pointers that belong to the kernel
- Added __start_opd and __end_opd pointers, to track the kernel
.opd section address range;

- Added dereference_kernel_function_descriptor(). Now we
will dereference only function pointers that are within
[__start_opd, __end_opd);

For pointers that belong to a module
- Added dereference_module_function_descriptor() to handle module
function descriptor dereference. Now we will dereference only
pointers that are within [module->opd.start, module->opd.end).

Link: http://lkml.kernel.org/r/[email protected]
To: Tony Luck <[email protected]>
To: Fenghua Yu <[email protected]>
To: Helge Deller <[email protected]>
To: Benjamin Herrenschmidt <[email protected]>
To: Paul Mackerras <[email protected]>
To: Michael Ellerman <[email protected]>
To: James Bottomley <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Jessica Yu <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Sergey Senozhatsky <[email protected]>
Tested-by: Helge Deller <[email protected]> #parisc64
Signed-off-by: Petr Mladek <[email protected]>

show more ...

mm, vmalloc: use __GFP_HIGHMEM implicitly

__vmalloc* allows users to provide gfp flags for the underlying
allocation. This API is quite popular

$ git grep "=[[:space:]]__vmalloc\|return[[:space:

mm, vmalloc: use __GFP_HIGHMEM implicitly

__vmalloc* allows users to provide gfp flags for the underlying
allocation. This API is quite popular

$ git grep "=[[:space:]]__vmalloc\|return[[:space:]]*__vmalloc" | wc -l
77

The only problem is that many people are not aware that they really want
to give __GFP_HIGHMEM along with other flags because there is really no
reason to consume precious lowmemory on CONFIG_HIGHMEM systems for pages
which are mapped to the kernel vmalloc space. About half of users don't
use this flag, though. This signals that we make the API unnecessarily
too complex.

This patch simply uses __GFP_HIGHMEM implicitly when allocating pages to
be mapped to the vmalloc space. Current users which add __GFP_HIGHMEM
are simplified and drop the flag.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Michal Hocko <[email protected]>
Reviewed-by: Matthew Wilcox <[email protected]>
Cc: Al Viro <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: Cristopher Lameter <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

parisc: support R_PARISC_SECREL32 relocation in modules

The parisc kernel doesn't work with CONFIG_MODVERSIONS since the commit
71810db27c1c853b335675bee335d893bc3d324b. It can't load modules with t

parisc: support R_PARISC_SECREL32 relocation in modules

The parisc kernel doesn't work with CONFIG_MODVERSIONS since the commit
71810db27c1c853b335675bee335d893bc3d324b. It can't load modules with the
error: "module unix: Unknown relocation: 41".

The commit changes __kcrctab from 64-bit valus to 32-bit values. The
assembler generates R_PARISC_SECREL32 secrel relocation for them and the
module loader doesn't support this relocation.

This patch adds the R_PARISC_SECREL32 relocation to the module loader.

Signed-off-by: Mikulas Patocka <[email protected]>
Cc: [email protected] # v4.10+
Signed-off-by: Helge Deller <[email protected]>

show more ...

parisc: Handle R_PARISC_PCREL32 relocations in kernel modules

Commit 0de7985 (parisc: Use generic extable search and sort routines)
changed the exception tables to use 32bit relative offsets.

This

parisc: Handle R_PARISC_PCREL32 relocations in kernel modules

Commit 0de7985 (parisc: Use generic extable search and sort routines)
changed the exception tables to use 32bit relative offsets.

This patch now adds support to the kernel module loader to handle such
R_PARISC_PCREL32 relocations for 32- and 64-bit modules.

Signed-off-by: Helge Deller <[email protected]>

show more ...

module: use a structure to encapsulate layout.

Makes it easier to handle init vs core cleanly, though the change is
fairly invasive across random architectures.

It simplifies the rbtree code immedi

module: use a structure to encapsulate layout.

Makes it easier to handle init vs core cleanly, though the change is
fairly invasive across random architectures.

It simplifies the rbtree code immediately, however, while keeping the
core data together in the same cachline (now iff the rbtree code is
enabled).

Acked-by: Peter Zijlstra <[email protected]>
Reviewed-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Rusty Russell <[email protected]>
Signed-off-by: Jiri Kosina <[email protected]>

show more ...

mm: vmalloc: pass additional vm_flags to __vmalloc_node_range()

For instrumenting global variables KASan will shadow memory backing memory
for modules. So on module loading we will need to allocate

mm: vmalloc: pass additional vm_flags to __vmalloc_node_range()

For instrumenting global variables KASan will shadow memory backing memory
for modules. So on module loading we will need to allocate memory for
shadow and map it at address in shadow that corresponds to the address
allocated in module_alloc().

__vmalloc_node_range() could be used for this purpose, except it puts a
guard hole after allocated area. Guard hole in shadow memory should be a
problem because at some future point we might need to have a shadow memory
at address occupied by guard hole. So we could fail to allocate shadow
for module_alloc().

Now we have VM_NO_GUARD flag disabling guard page, so we need to pass into
__vmalloc_node_range(). Add new parameter 'vm_flags' to
__vmalloc_node_range() function.

Signed-off-by: Andrey Ryabinin <[email protected]>
Cc: Dmitry Vyukov <[email protected]>
Cc: Konstantin Serebryany <[email protected]>
Cc: Dmitry Chernenkov <[email protected]>
Signed-off-by: Andrey Konovalov <[email protected]>
Cc: Yuri Gribov <[email protected]>
Cc: Konstantin Khlebnikov <[email protected]>
Cc: Sasha Levin <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Joonsoo Kim <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Pekka Enberg <[email protected]>
Cc: David Rientjes <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

module_arch_freeing_init(): new hook for archs before module->module_init freed.

Archs have been abusing module_free() to clean up their arch-specific
allocations. Since module_free() is also (ab)u

module_arch_freeing_init(): new hook for archs before module->module_init freed.

Archs have been abusing module_free() to clean up their arch-specific
allocations. Since module_free() is also (ab)used by BPF and trace code,
let's keep it to simple allocations, and provide a hook called before
that.

This means that avr32, ia64, parisc and s390 no longer need to implement
their own module_free() at all. avr32 doesn't need module_finalize()
either.

Signed-off-by: Rusty Russell <[email protected]>
Cc: Chris Metcalf <[email protected]>
Cc: Haavard Skinnemoen <[email protected]>
Cc: Hans-Christian Egtvedt <[email protected]>
Cc: Tony Luck <[email protected]>
Cc: Fenghua Yu <[email protected]>
Cc: "James E.J. Bottomley" <[email protected]>
Cc: Helge Deller <[email protected]>
Cc: Martin Schwidefsky <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]

show more ...

mm/arch: use NUMA_NO_NODE

Use more appropriate NUMA_NO_NODE instead of -1 in all archs' module_alloc()

Signed-off-by: Jianguo Wu <[email protected]>
Acked-by: David Rientjes <[email protected]

mm/arch: use NUMA_NO_NODE

Use more appropriate NUMA_NO_NODE instead of -1 in all archs' module_alloc()

Signed-off-by: Jianguo Wu <[email protected]>
Acked-by: David Rientjes <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

modules: don't hand 0 to vmalloc.

In commit d0a21265dfb5fa8a David Rientjes unified various archs'
module_alloc implementation (including x86) and removed the graduitous
shortcut for size == 0.

The

modules: don't hand 0 to vmalloc.

In commit d0a21265dfb5fa8a David Rientjes unified various archs'
module_alloc implementation (including x86) and removed the graduitous
shortcut for size == 0.

Then, in commit de7d2b567d040e3b, Joe Perches added a warning for
zero-length vmallocs, which can happen without kallsyms on modules
with no init sections (eg. zlib_deflate).

Fix this once and for all; the module code has to handle zero length
anyway, so get it right at the caller and remove the now-gratuitous
checks within the arch-specific module_alloc implementations.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=42608
Reported-by: Conrad Kostecki <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: Joe Perches <[email protected]>
Signed-off-by: Rusty Russell <[email protected]>

show more ...

modules: make arch's use default loader hooks

This patch removes all the module loader hook implementations in the
architecture specific code where the functionality is the same as that
now provided

modules: make arch's use default loader hooks

This patch removes all the module loader hook implementations in the
architecture specific code where the functionality is the same as that
now provided by the recently added default hooks.

Signed-off-by: Jonas Bonn <[email protected]>
Acked-by: Mike Frysinger <[email protected]>
Acked-by: Geert Uytterhoeven <[email protected]>
Tested-by: Michal Simek <[email protected]>
Signed-off-by: Rusty Russell <[email protected]>

show more ...

[PARISC] only make executable areas executable

Currently parisc has the whole kernel marked as RWX, meaning any
kernel page at all is eligible to be executed. This can cause a
theoretical problem o

[PARISC] only make executable areas executable

Currently parisc has the whole kernel marked as RWX, meaning any
kernel page at all is eligible to be executed. This can cause a
theoretical problem on systems with combined I/D TLB because the act
of referencing a page causes a TLB insertion with an executable bit.
This TLB entry may be used by the CPU as the basis for speculating the
page into the I-Cache. If this speculated page is subsequently used
for a user process, there is the possibility we will get a stale
I-cache line picked up as the binary executes.

As a point of good practise, only mark actual kernel text pages as
executable. The same has to be done for init_text pages, but they're
converted to data pages (and the I-Cache flushed) when the init memory
is released.

Signed-off-by: James Bottomley <[email protected]>

show more ...

modules: Fix module_bug_list list corruption race

With all the recent module loading cleanups, we've minimized the code
that sits under module_mutex, fixing various deadlocks and making it
possible

modules: Fix module_bug_list list corruption race

With all the recent module loading cleanups, we've minimized the code
that sits under module_mutex, fixing various deadlocks and making it
possible to do most of the module loading in parallel.

However, that whole conversion totally missed the rather obscure code
that adds a new module to the list for BUG() handling. That code was
doubly obscure because (a) the code itself lives in lib/bugs.c (for
dubious reasons) and (b) it gets called from the architecture-specific
"module_finalize()" rather than from generic code.

Calling it from arch-specific code makes no sense what-so-ever to begin
with, and is now actively wrong since that code isn't protected by the
module loading lock any more.

So this commit moves the "module_bug_{finalize,cleanup}()" calls away
from the arch-specific code, and into the generic code - and in the
process protects it with the module_mutex so that the list operations
are now safe.

Future fixups:
- move the module list handling code into kernel/module.c where it
belongs.
- get rid of 'module_bug_list' and just use the regular list of modules
(called 'modules' - imagine that) that we already create and maintain
for other reasons.

Reported-and-tested-by: Thomas Gleixner <[email protected]>
Cc: Rusty Russell <[email protected]>
Cc: Adrian Bunk <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: [email protected]
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when bu

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.

2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).

* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <[email protected]>
Guess-its-ok-by: Christoph Lameter <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Lee Schermerhorn <[email protected]>

show more ...