Add the running kernel's build ID[1] to the stacktrace information header.
This makes it simpler for developers to locate the vmlinux with full
debuginfo for a particular kernel stacktrace. Combined with
scripts/decode_stracktrace.sh, a developer can download the correct
vmlinux from a debuginfod[2] server and find the exact file and line
number for the functions plus offsets in a stacktrace.
This is especially useful for pstore crash debugging where the kernel
crashes are recorded in the pstore logs and the recovery kernel is
different or the debuginfo doesn't exist on the device due to space
concerns (the data can be large and a security concern). The stacktrace
can be analyzed after the crash by using the build ID to find the matching
vmlinux and understand where in the function something went wrong.
Example stacktrace from lkdtm:
WARNING: CPU: 4 PID: 3255 at drivers/misc/lkdtm/bugs.c:83 lkdtm_WARNING+0x28/0x30 [lkdtm]
Modules linked in: lkdtm rfcomm algif_hash algif_skcipher af_alg xt_cgroup uinput xt_MASQUERADE
CPU: 4 PID: 3255 Comm: bash Not tainted 5.11 #3 aa23f7a1231c229de205662d5a9e0d4c580f19a1
Hardware name: Google Lazor (rev3+) with KB Backlight (DT)
pstate: 00400009 (nzcv daif +PAN -UAO -TCO BTYPE=--)
pc : lkdtm_WARNING+0x28/0x30 [lkdtm]
The hex string aa23f7a1231c229de205662d5a9e0d4c580f19a1 is the build ID,
following the kernel version number. Put it all behind a config option,
STACKTRACE_BUILD_ID, so that kernel developers can remove this
information if they decide it is too much.
Link: https://lkml.kernel.org/r/20210511003845.2429846-5-swboyd@chromium.org
Link: https://fedoraproject.org/wiki/Releases/FeatureBuildId [1]
Link: https://sourceware.org/elfutils/Debuginfod.html [2]
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Evan Green <evgreen@chromium.org>
Cc: Hsin-Yi Wang <hsinyi@chromium.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "Add build ID to stacktraces", v6.
This series adds the kernel's build ID[1] to the stacktrace header printed
in oops messages, warnings, etc. and the build ID for any module that
appears in the stacktrace after the module name. The goal is to make the
stacktrace more self-contained and descriptive by including the relevant
build IDs in the kernel logs when something goes wrong. This can be used
by post processing tools like script/decode_stacktrace.sh and kernel
developers to easily locate the debug info associated with a kernel crash
and line up what line and file things started falling apart at.
To show how this can be used I've included a patch to decode_stacktrace.sh
that downloads the debuginfo from a debuginfod server. This also includes
some patches to make the buildid.c file use more const arguments and
consolidate logic into buildid.c from kdump. These are left to the end as
they were mostly cleanup patches.
Here's an example lkdtm stacktrace on arm64.
WARNING: CPU: 4 PID: 3255 at drivers/misc/lkdtm/bugs.c:83 lkdtm_WARNING+0x28/0x30 [lkdtm]
Modules linked in: lkdtm rfcomm algif_hash algif_skcipher af_alg xt_cgroup uinput xt_MASQUERADE
CPU: 4 PID: 3255 Comm: bash Not tainted 5.11 #3 aa23f7a1231c229de205662d5a9e0d4c580f19a1
Hardware name: Google Lazor (rev3+) with KB Backlight (DT)
pstate: 00400009 (nzcv daif +PAN -UAO -TCO BTYPE=--)
pc : lkdtm_WARNING+0x28/0x30 [lkdtm]
lr : lkdtm_do_action+0x24/0x40 [lkdtm]
sp : ffffffc0134fbca0
x29: ffffffc0134fbca0 x28: ffffff92d53ba240
x27: 0000000000000000 x26: 0000000000000000
x25: 0000000000000000 x24: ffffffe3622352c0
x23: 0000000000000020 x22: ffffffe362233366
x21: ffffffe3622352e0 x20: ffffffc0134fbde0
x19: 0000000000000008 x18: 0000000000000000
x17: ffffff929b6536fc x16: 0000000000000000
x15: 0000000000000000 x14: 0000000000000012
x13: ffffffe380ed892c x12: ffffffe381d05068
x11: 0000000000000000 x10: 0000000000000000
x9 : 0000000000000001 x8 : ffffffe362237000
x7 : aaaaaaaaaaaaaaaa x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000001
x3 : 0000000000000008 x2 : ffffff93fef25a70
x1 : ffffff93fef15788 x0 : ffffffe3622352e0
Call trace:
lkdtm_WARNING+0x28/0x30 [lkdtm ed5019fdf5e53be37cb1ba7899292d7e143b259e]
direct_entry+0x16c/0x1b4 [lkdtm ed5019fdf5e53be37cb1ba7899292d7e143b259e]
full_proxy_write+0x74/0xa4
vfs_write+0xec/0x2e8
ksys_write+0x84/0xf0
__arm64_sys_write+0x24/0x30
el0_svc_common+0xf4/0x1c0
do_el0_svc_compat+0x28/0x3c
el0_svc_compat+0x10/0x1c
el0_sync_compat_handler+0xa8/0xcc
el0_sync_compat+0x178/0x180
---[ end trace 3d95032303e59e68 ]---
This patch (of 13):
Some kernel elf files have various notes that also happen to have an elf
note type of '3', which matches NT_GNU_BUILD_ID but the note name isn't
"GNU". For example, this note trips up the existing logic:
Owner Data size Description
Xen 0x00000008 Unknown note type: (0x00000003) description data: 00 00 00 ffffff80 ffffffff ffffffff ffffffff ffffffff
Let's make sure that it is a GNU note when parsing the build ID so that we
can use this function to parse a vmlinux's build ID too.
Link: https://lkml.kernel.org/r/20210511003845.2429846-1-swboyd@chromium.org
Link: https://lkml.kernel.org/r/20210511003845.2429846-2-swboyd@chromium.org
Fixes: bd7525dacd ("bpf: Move stack_map_get_build_id into lib")
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Reported-by: Petr Mladek <pmladek@suse.com>
Tested-by: Petr Mladek <pmladek@suse.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Evan Green <evgreen@chromium.org>
Cc: Hsin-Yi Wang <hsinyi@chromium.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Introduce "memfd_secret" system call with the ability to create memory
areas visible only in the context of the owning process and not mapped not
only to other processes but in the kernel page tables as well.
The secretmem feature is off by default and the user must explicitly
enable it at the boot time.
Once secretmem is enabled, the user will be able to create a file
descriptor using the memfd_secret() system call. The memory areas created
by mmap() calls from this file descriptor will be unmapped from the kernel
direct map and they will be only mapped in the page table of the processes
that have access to the file descriptor.
Secretmem is designed to provide the following protections:
* Enhanced protection (in conjunction with all the other in-kernel
attack prevention systems) against ROP attacks. Seceretmem makes
"simple" ROP insufficient to perform exfiltration, which increases the
required complexity of the attack. Along with other protections like
the kernel stack size limit and address space layout randomization which
make finding gadgets is really hard, absence of any in-kernel primitive
for accessing secret memory means the one gadget ROP attack can't work.
Since the only way to access secret memory is to reconstruct the missing
mapping entry, the attacker has to recover the physical page and insert
a PTE pointing to it in the kernel and then retrieve the contents. That
takes at least three gadgets which is a level of difficulty beyond most
standard attacks.
* Prevent cross-process secret userspace memory exposures. Once the
secret memory is allocated, the user can't accidentally pass it into the
kernel to be transmitted somewhere. The secreremem pages cannot be
accessed via the direct map and they are disallowed in GUP.
* Harden against exploited kernel flaws. In order to access secretmem,
a kernel-side attack would need to either walk the page tables and
create new ones, or spawn a new privileged uiserspace process to perform
secrets exfiltration using ptrace.
The file descriptor based memory has several advantages over the
"traditional" mm interfaces, such as mlock(), mprotect(), madvise(). File
descriptor approach allows explicit and controlled sharing of the memory
areas, it allows to seal the operations. Besides, file descriptor based
memory paves the way for VMMs to remove the secret memory range from the
userspace hipervisor process, for instance QEMU. Andy Lutomirski says:
"Getting fd-backed memory into a guest will take some possibly major
work in the kernel, but getting vma-backed memory into a guest without
mapping it in the host user address space seems much, much worse."
memfd_secret() is made a dedicated system call rather than an extension to
memfd_create() because it's purpose is to allow the user to create more
secure memory mappings rather than to simply allow file based access to
the memory. Nowadays a new system call cost is negligible while it is way
simpler for userspace to deal with a clear-cut system calls than with a
multiplexer or an overloaded syscall. Moreover, the initial
implementation of memfd_secret() is completely distinct from
memfd_create() so there is no much sense in overloading memfd_create() to
begin with. If there will be a need for code sharing between these
implementation it can be easily achieved without a need to adjust user
visible APIs.
The secret memory remains accessible in the process context using uaccess
primitives, but it is not exposed to the kernel otherwise; secret memory
areas are removed from the direct map and functions in the
follow_page()/get_user_page() family will refuse to return a page that
belongs to the secret memory area.
Once there will be a use case that will require exposing secretmem to the
kernel it will be an opt-in request in the system call flags so that user
would have to decide what data can be exposed to the kernel.
Removing of the pages from the direct map may cause its fragmentation on
architectures that use large pages to map the physical memory which
affects the system performance. However, the original Kconfig text for
CONFIG_DIRECT_GBPAGES said that gigabyte pages in the direct map "... can
improve the kernel's performance a tiny bit ..." (commit 00d1c5e057
("x86: add gbpages switches")) and the recent report [1] showed that "...
although 1G mappings are a good default choice, there is no compelling
evidence that it must be the only choice". Hence, it is sufficient to
have secretmem disabled by default with the ability of a system
administrator to enable it at boot time.
Pages in the secretmem regions are unevictable and unmovable to avoid
accidental exposure of the sensitive data via swap or during page
migration.
Since the secretmem mappings are locked in memory they cannot exceed
RLIMIT_MEMLOCK. Since these mappings are already locked independently
from mlock(), an attempt to mlock()/munlock() secretmem range would fail
and mlockall()/munlockall() will ignore secretmem mappings.
However, unlike mlock()ed memory, secretmem currently behaves more like
long-term GUP: secretmem mappings are unmovable mappings directly consumed
by user space. With default limits, there is no excessive use of
secretmem and it poses no real problem in combination with
ZONE_MOVABLE/CMA, but in the future this should be addressed to allow
balanced use of large amounts of secretmem along with ZONE_MOVABLE/CMA.
A page that was a part of the secret memory area is cleared when it is
freed to ensure the data is not exposed to the next user of that page.
The following example demonstrates creation of a secret mapping (error
handling is omitted):
fd = memfd_secret(0);
ftruncate(fd, MAP_SIZE);
ptr = mmap(NULL, MAP_SIZE, PROT_READ | PROT_WRITE,
MAP_SHARED, fd, 0);
[1] https://lore.kernel.org/linux-mm/213b4567-46ce-f116-9cdf-bbd0c884eb3c@linux.intel.com/
[akpm@linux-foundation.org: suppress Kconfig whine]
Link: https://lkml.kernel.org/r/20210518072034.31572-5-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Hagen Paul Pfeifer <hagen@jauu.net>
Acked-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christopher Lameter <cl@linux.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Palmer Dabbelt <palmerdabbelt@google.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rick Edgecombe <rick.p.edgecombe@intel.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tycho Andersen <tycho@tycho.ws>
Cc: Will Deacon <will@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: kernel test robot <lkp@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "mm: introduce memfd_secret system call to create "secret" memory areas", v20.
This is an implementation of "secret" mappings backed by a file
descriptor.
The file descriptor backing secret memory mappings is created using a
dedicated memfd_secret system call The desired protection mode for the
memory is configured using flags parameter of the system call. The mmap()
of the file descriptor created with memfd_secret() will create a "secret"
memory mapping. The pages in that mapping will be marked as not present
in the direct map and will be present only in the page table of the owning
mm.
Although normally Linux userspace mappings are protected from other users,
such secret mappings are useful for environments where a hostile tenant is
trying to trick the kernel into giving them access to other tenants
mappings.
It's designed to provide the following protections:
* Enhanced protection (in conjunction with all the other in-kernel
attack prevention systems) against ROP attacks. Seceretmem makes
"simple" ROP insufficient to perform exfiltration, which increases the
required complexity of the attack. Along with other protections like
the kernel stack size limit and address space layout randomization which
make finding gadgets is really hard, absence of any in-kernel primitive
for accessing secret memory means the one gadget ROP attack can't work.
Since the only way to access secret memory is to reconstruct the missing
mapping entry, the attacker has to recover the physical page and insert
a PTE pointing to it in the kernel and then retrieve the contents. That
takes at least three gadgets which is a level of difficulty beyond most
standard attacks.
* Prevent cross-process secret userspace memory exposures. Once the
secret memory is allocated, the user can't accidentally pass it into the
kernel to be transmitted somewhere. The secreremem pages cannot be
accessed via the direct map and they are disallowed in GUP.
* Harden against exploited kernel flaws. In order to access secretmem,
a kernel-side attack would need to either walk the page tables and
create new ones, or spawn a new privileged uiserspace process to perform
secrets exfiltration using ptrace.
In the future the secret mappings may be used as a mean to protect guest
memory in a virtual machine host.
For demonstration of secret memory usage we've created a userspace library
https://git.kernel.org/pub/scm/linux/kernel/git/jejb/secret-memory-preloader.git
that does two things: the first is act as a preloader for openssl to
redirect all the OPENSSL_malloc calls to secret memory meaning any secret
keys get automatically protected this way and the other thing it does is
expose the API to the user who needs it. We anticipate that a lot of the
use cases would be like the openssl one: many toolkits that deal with
secret keys already have special handling for the memory to try to give
them greater protection, so this would simply be pluggable into the
toolkits without any need for user application modification.
Hiding secret memory mappings behind an anonymous file allows usage of the
page cache for tracking pages allocated for the "secret" mappings as well
as using address_space_operations for e.g. page migration callbacks.
The anonymous file may be also used implicitly, like hugetlb files, to
implement mmap(MAP_SECRET) and use the secret memory areas with "native"
mm ABIs in the future.
Removing of the pages from the direct map may cause its fragmentation on
architectures that use large pages to map the physical memory which
affects the system performance. However, the original Kconfig text for
CONFIG_DIRECT_GBPAGES said that gigabyte pages in the direct map "... can
improve the kernel's performance a tiny bit ..." (commit 00d1c5e057
("x86: add gbpages switches")) and the recent report [1] showed that "...
although 1G mappings are a good default choice, there is no compelling
evidence that it must be the only choice". Hence, it is sufficient to
have secretmem disabled by default with the ability of a system
administrator to enable it at boot time.
In addition, there is also a long term goal to improve management of the
direct map.
[1] https://lore.kernel.org/linux-mm/213b4567-46ce-f116-9cdf-bbd0c884eb3c@linux.intel.com/
This patch (of 7):
It will be used by the upcoming secret memory implementation.
Link: https://lkml.kernel.org/r/20210518072034.31572-1-rppt@kernel.org
Link: https://lkml.kernel.org/r/20210518072034.31572-2-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christopher Lameter <cl@linux.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: Hagen Paul Pfeifer <hagen@jauu.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Palmer Dabbelt <palmerdabbelt@google.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rick Edgecombe <rick.p.edgecombe@intel.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tycho Andersen <tycho@tycho.ws>
Cc: Will Deacon <will@kernel.org>
Cc: kernel test robot <lkp@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ld.lld warns that the '.modinfo' section is not currently handled:
ld.lld: warning: kernel/built-in.a(workqueue.o):(.modinfo) is being placed in '.modinfo'
ld.lld: warning: kernel/built-in.a(printk/printk.o):(.modinfo) is being placed in '.modinfo'
ld.lld: warning: kernel/built-in.a(irq/spurious.o):(.modinfo) is being placed in '.modinfo'
ld.lld: warning: kernel/built-in.a(rcu/update.o):(.modinfo) is being placed in '.modinfo'
The '.modinfo' section was added in commit 898490c010 ("moduleparam:
Save information about built-in modules in separate file") to the DISCARDS
macro but Hexagon has never used that macro. The unification of DISCARDS
happened in commit 023bf6f1b8 ("linker script: unify usage of discard
definition") in 2009, prior to Hexagon being added in 2011.
Switch Hexagon over to the DISCARDS macro so that anything that is
expected to be discarded gets discarded.
Link: https://lkml.kernel.org/r/20210521011239.1332345-3-nathan@kernel.org
Fixes: e95bf452a9 ("Hexagon: Add configuration and makefiles for the Hexagon architecture.")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Brian Cain <bcain@codeaurora.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Oliver Glitta <glittao@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "hexagon: Fix build error with CONFIG_STACKDEPOT and select CONFIG_ARCH_WANT_LD_ORPHAN_WARN".
This series fixes an error with ARCH=hexagon that was pointed out by the
patch "mm/slub: use stackdepot to save stack trace in objects".
The first patch fixes that error by handling the '.irqentry.text' and
'.softirqentry.text' sections.
The second patch switches Hexagon over to the common DISCARDS macro, which
should have been done when Hexagon was merged into the tree to match
commit 023bf6f1b8 ("linker script: unify usage of discard definition").
The third patch selects CONFIG_ARCH_WANT_LD_ORPHAN_WARN so that something
like this does not happen again.
This patch (of 3):
Patch "mm/slub: use stackdepot to save stack trace in objects" in -mm
selects CONFIG_STACKDEPOT when CONFIG_STACKTRACE_SUPPORT is selected and
CONFIG_STACKDEPOT requires IRQENTRY_TEXT and SOFTIRQENTRY_TEXT to be
handled after commit 505a0ef15f ("kasan: stackdepot: move
filter_irq_stacks() to stackdepot.c") due to the use of the
__{,soft}irqentry_text_{start,end} section symbols. If those sections are
not handled, the build is broken.
$ make ARCH=hexagon CROSS_COMPILE=hexagon-linux- LLVM=1 LLVM_IAS=1 defconfig all
...
ld.lld: error: undefined symbol: __irqentry_text_start
>>> referenced by stackdepot.c
>>> stackdepot.o:(filter_irq_stacks) in archive lib/built-in.a
>>> referenced by stackdepot.c
>>> stackdepot.o:(filter_irq_stacks) in archive lib/built-in.a
ld.lld: error: undefined symbol: __irqentry_text_end
>>> referenced by stackdepot.c
>>> stackdepot.o:(filter_irq_stacks) in archive lib/built-in.a
>>> referenced by stackdepot.c
>>> stackdepot.o:(filter_irq_stacks) in archive lib/built-in.a
ld.lld: error: undefined symbol: __softirqentry_text_start
>>> referenced by stackdepot.c
>>> stackdepot.o:(filter_irq_stacks) in archive lib/built-in.a
>>> referenced by stackdepot.c
>>> stackdepot.o:(filter_irq_stacks) in archive lib/built-in.a
ld.lld: error: undefined symbol: __softirqentry_text_end
>>> referenced by stackdepot.c
>>> stackdepot.o:(filter_irq_stacks) in archive lib/built-in.a
>>> referenced by stackdepot.c
>>> stackdepot.o:(filter_irq_stacks) in archive lib/built-in.a
...
Add these sections to the Hexagon linker script so the build continues to
work. ld.lld's orphan section warning would have caught this prior to the
-mm commit mentioned above:
ld.lld: warning: kernel/built-in.a(softirq.o):(.softirqentry.text) is being placed in '.softirqentry.text'
ld.lld: warning: kernel/built-in.a(softirq.o):(.softirqentry.text) is being placed in '.softirqentry.text'
ld.lld: warning: kernel/built-in.a(softirq.o):(.softirqentry.text) is being placed in '.softirqentry.text'
Link: https://lkml.kernel.org/r/20210521011239.1332345-1-nathan@kernel.org
Link: https://lkml.kernel.org/r/20210521011239.1332345-2-nathan@kernel.org
Link: https://github.com/ClangBuiltLinux/linux/issues/1381
Fixes: 505a0ef15f ("kasan: stackdepot: move filter_irq_stacks() to stackdepot.c")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Brian Cain <bcain@codeaurora.org>
Cc: Oliver Glitta <glittao@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix some spelling mistakes in comments found by "codespell":
Hoever ==> However
poiter ==> pointer
representaion ==> representation
uppon ==> upon
independend ==> independent
aquired ==> acquired
mis-match ==> mismatch
scrach ==> scratch
struture ==> structure
Analagous ==> Analogous
interation ==> iteration
And some were discovered manually by Joe Perches and Christoph Lameter:
stroed ==> stored
arch independent ==> an architecture independent
A example structure for ==> Example structure for
Link: https://lkml.kernel.org/r/20210609150027.14805-2-thunder.leizhen@huawei.com
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Cc: Christoph Lameter <cl@gentwo.de>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull module updates from Jessica Yu:
- Fix incorrect logic in module_kallsyms_on_each_symbol()
- Fix for a Coccinelle warning
* tag 'modules-for-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
module: correctly exit module_kallsyms_on_each_symbol when fn() != 0
kernel/module: Use BUG_ON instead of if condition followed by BUG
Pull x86 fpu updates from Thomas Gleixner:
"Fixes and improvements for FPU handling on x86:
- Prevent sigaltstack out of bounds writes.
The kernel unconditionally writes the FPU state to the alternate
stack without checking whether the stack is large enough to
accomodate it.
Check the alternate stack size before doing so and in case it's too
small force a SIGSEGV instead of silently corrupting user space
data.
- MINSIGSTKZ and SIGSTKSZ are constants in signal.h and have never
been updated despite the fact that the FPU state which is stored on
the signal stack has grown over time which causes trouble in the
field when AVX512 is available on a CPU. The kernel does not expose
the minimum requirements for the alternate stack size depending on
the available and enabled CPU features.
ARM already added an aux vector AT_MINSIGSTKSZ for the same reason.
Add it to x86 as well.
- A major cleanup of the x86 FPU code. The recent discoveries of
XSTATE related issues unearthed quite some inconsistencies,
duplicated code and other issues.
The fine granular overhaul addresses this, makes the code more
robust and maintainable, which allows to integrate upcoming XSTATE
related features in sane ways"
* tag 'x86-fpu-2021-07-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (74 commits)
x86/fpu/xstate: Clear xstate header in copy_xstate_to_uabi_buf() again
x86/fpu/signal: Let xrstor handle the features to init
x86/fpu/signal: Handle #PF in the direct restore path
x86/fpu: Return proper error codes from user access functions
x86/fpu/signal: Split out the direct restore code
x86/fpu/signal: Sanitize copy_user_to_fpregs_zeroing()
x86/fpu/signal: Sanitize the xstate check on sigframe
x86/fpu/signal: Remove the legacy alignment check
x86/fpu/signal: Move initial checks into fpu__restore_sig()
x86/fpu: Mark init_fpstate __ro_after_init
x86/pkru: Remove xstate fiddling from write_pkru()
x86/fpu: Don't store PKRU in xstate in fpu_reset_fpstate()
x86/fpu: Remove PKRU handling from switch_fpu_finish()
x86/fpu: Mask PKRU from kernel XRSTOR[S] operations
x86/fpu: Hook up PKRU into ptrace()
x86/fpu: Add PKRU storage outside of task XSAVE buffer
x86/fpu: Dont restore PKRU in fpregs_restore_userspace()
x86/fpu: Rename xfeatures_mask_user() to xfeatures_mask_uabi()
x86/fpu: Move FXSAVE_LEAK quirk info __copy_kernel_to_fpregs()
x86/fpu: Rename __fpregs_load_activate() to fpregs_restore_userregs()
...
Pull xen updates from Juergen Gross:
"Only two minor patches this time: one cleanup patch and one patch
refreshing a Xen header"
* tag 'for-linus-5.14-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen: sync include/xen/interface/io/ring.h with Xen's newest version
xen: Use DEVICE_ATTR_*() macro
Pull more fallthrough fixes from Gustavo Silva:
"Fix maore fall-through warnings when building the kernel with clang
and '-Wimplicit-fallthrough'"
* tag 'Wimplicit-fallthrough-clang-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux:
Input: Fix fall-through warning for Clang
scsi: aic94xx: Fix fall-through warning for Clang
i3c: master: cdns: Fix fall-through warning for Clang
net/mlx4: Fix fall-through warning for Clang
Pull hwspinlock updates from Bjorn Andersson:
"This adds a driver for the hardware spinlock in Allwinner sun6i"
* tag 'hwlock-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/andersson/remoteproc:
dt-bindings: hwlock: sun6i: Fix various warnings in binding
hwspinlock: add sun6i hardware spinlock support
dt-bindings: hwlock: add sun6i_hwspinlock
Pull remoteproc updates from Bjorn Andersson:
"This adds support for controlling the PRU and R5F clusters on the TI
AM64x, the remote processor in i.MX7ULP, i.MX8MN/P and i.MX8ULP NXP
and the audio, compute and modem remoteprocs in the Qualcomm SC8180x
platform.
It fixes improper ordering of cdev and device creation of the
remoteproc control interface and it fixes resource leaks in the error
handling path of rproc_add() and the Qualcomm modem and wifi
remoteproc drivers.
Lastly it fixes a few build warnings and replace the dummy parameter
passed in the mailbox api of the stm32 driver to something not living
on the stack"
* tag 'rproc-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/andersson/remoteproc: (32 commits)
remoteproc: qcom: pas: Add SC8180X adsp, cdsp and mpss
dt-bindings: remoteproc: qcom: pas: Add SC8180X adsp, cdsp and mpss
remoteproc: imx_rproc: support i.MX8ULP
dt-bindings: remoteproc: imx_rproc: support i.MX8ULP
remoteproc: stm32: fix mbox_send_message call
remoteproc: core: Cleanup device in case of failure
remoteproc: core: Fix cdev remove and rproc del
remoteproc: core: Move validate before device add
remoteproc: core: Move cdev add before device add
remoteproc: pru: Add support for various PRU cores on K3 AM64x SoCs
dt-bindings: remoteproc: pru: Update bindings for K3 AM64x SoCs
remoteproc: qcom_wcnss: Use devm_qcom_smem_state_get()
remoteproc: qcom_q6v5: Use devm_qcom_smem_state_get() to fix missing put()
soc: qcom: smem_state: Add devm_qcom_smem_state_get()
dt-bindings: remoteproc: qcom: pas: Fix indentation warnings
remoteproc: imx-rproc: Fix IMX_REMOTEPROC configuration
remoteproc: imx_rproc: support i.MX8MN/P
remoteproc: imx_rproc: support i.MX7ULP
remoteproc: imx_rproc: make clk optional
remoteproc: imx_rproc: initial support for mutilple start/stop method
...
In preparation to enable -Wimplicit-fallthrough for Clang, fix a
warning by explicitly adding a fallthrough; statement.
Notice that this seems to be a Duff device for performance[1]. So,
although the code looks a bit _funny_, I didn't want to refactor
or modify it beyond merely adding a fallthrough marking, which
might be the least disruptive way to fix this issue.
[1] https://www.drdobbs.com/a-reusable-duff-device/184406208
Link: https://github.com/KSPP/linux/issues/115
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
In preparation to enable -Wimplicit-fallthrough for Clang, fix a
warning by explicitly adding a fallthrough; statement.
Notice that this seems to be a Duff device for performance[1]. So,
although the code looks a bit _funny_, I didn't want to refactor
or modify it beyond merely adding a fallthrough marking, which
might be the least disruptive way to fix this issue.
[1] https://www.drdobbs.com/a-reusable-duff-device/184406208
Link: https://github.com/KSPP/linux/issues/115
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Pull ARM development updates from Russell King:
- Make it clear __swp_entry_to_pte() uses PTE_TYPE_FAULT
- Updates for setting vmalloc size via command line to resolve an issue
with the 8MiB hole not properly being accounted for, and clean up the
code.
- ftrace support for module PLTs
- Spelling fixes
- kbuild updates for removing generated files and pattern rules for
generating files
- Clang/llvm updates
- Change the way the kernel is mapped, placing it in vmalloc space
instead.
- Remove arm_pm_restart from arm and aarch64.
* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: (29 commits)
ARM: 9098/1: ftrace: MODULE_PLT: Fix build problem without DYNAMIC_FTRACE
ARM: 9097/1: mmu: Declare section start/end correctly
ARM: 9096/1: Remove arm_pm_restart()
ARM: 9095/1: ARM64: Remove arm_pm_restart()
ARM: 9094/1: Register with kernel restart handler
ARM: 9093/1: drivers: firmwapsci: Register with kernel restart handler
ARM: 9092/1: xen: Register with kernel restart handler
ARM: 9091/1: Revert "mm: qsd8x50: Fix incorrect permission faults"
ARM: 9090/1: Map the lowmem and kernel separately
ARM: 9089/1: Define kernel physical section start and end
ARM: 9088/1: Split KERNEL_OFFSET from PAGE_OFFSET
ARM: 9087/1: kprobes: test-thumb: fix for LLVM_IAS=1
ARM: 9086/1: syscalls: use pattern rules to generate syscall headers
ARM: 9085/1: remove unneeded abi parameter to syscallnr.sh
ARM: 9084/1: simplify the build rule of mach-types.h
ARM: 9083/1: uncompress: atags_to_fdt: Spelling s/REturn/Return/
ARM: 9082/1: [v2] mark prepare_page_table as __init
ARM: 9079/1: ftrace: Add MODULE_PLTS support
ARM: 9078/1: Add warn suppress parameter to arm_gen_branch_link()
ARM: 9077/1: PLT: Move struct plt_entries definition to header
...
Pull OpenRISC updates from Stafford Horne:
"One change to simplify Litex CSR (MMIO register) access by limiting
them to 32-bit offsets.
Now that this is agreed on among Litex hardware and kernel developers
it will allow us to start upstreaming other Litex peripheral drivers"
* tag 'for-linus' of git://github.com/openrisc/linux:
drivers/soc/litex: remove 8-bit subregister option
Pull kgdb updates from Daniel Thompson:
"This was a extremely quiet cycle for kgdb. This consists of two
patches that between them address spelling errors and a switch
fallthrough warning"
* tag 'kgdb-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux:
kgdb: Fix fall-through warning for Clang
kgdb: Fix spelling mistakes
Pull coccinelle updates from Julia Lawall:
"There are two new semantic patches:
- minmax: To use min and max instead of ? :
- swap: To use swap when possible
Some other semantic patches have been updated to better conform to
Linux kernel developer expectations or to make the explanation message
more clear.
Finally, there is a fix for the coccicheck script"
* 'for-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/jlawall/linux:
coccinelle: api: remove kobj_to_dev.cocci script
scripts: coccicheck: fix troubles on non-English builds
coccinelle: misc: minmax: suppress patch generation for err returns
drop unneeded *s
coccinelle: irqf_oneshot: reduce the severity due to false positives
coccinelle: misc: add swap script
coccinelle: misc: update uninitialized_var.cocci documentation
coccinelle: misc: restrict patch mode in flexible_array.cocci
coccinelle: misc: add minmax script
Pull fuse updates from Miklos Szeredi:
- Fixes for virtiofs submounts
- Misc fixes and cleanups
* tag 'fuse-update-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
virtiofs: Fix spelling mistakes
fuse: use DIV_ROUND_UP helper macro for calculations
fuse: fix illegal access to inode with reused nodeid
fuse: allow fallocate(FALLOC_FL_ZERO_RANGE)
fuse: Make fuse_fill_super_submount() static
fuse: Switch to fc_mount() for submounts
fuse: Call vfs_get_tree() for submounts
fuse: add dedicated filesystem context ops for submounts
virtiofs: propagate sync() to file server
fuse: reject internal errno
fuse: check connected before queueing on fpq->io
fuse: ignore PG_workingset after stealing
fuse: Fix infinite loop in sget_fc()
fuse: Fix crash if superblock of submount gets killed early
fuse: Fix crash in fuse_dentry_automount() error path
Pull orangefs updates from Mike Marshall:
"A read-ahead adjustment and a fix.
The readahead adjustment was suggested by Matthew Wilcox and looks
like how I should have written it in the first place... the "df fix"
was suggested by Walt Ligon, some Orangefs users have been complaining
about whacky df output..."
* tag 'for-linus-5.14-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux:
orangefs: fix orangefs df output.
orangefs: readahead adjustment
Pull exfat updates from Namjae Jeon:
- Improved compatibility issue with exfat from some camera vendors.
- Do not need to release root inode on error path.
* tag 'exfat-for-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat:
exfat: handle wrong stream entry size in exfat_readdir()
exfat: avoid incorrectly releasing for root inode
Pull USB / Thunderbolt updates from Greg KH:
"Here is the big set of USB and Thunderbolt patches for 5.14-rc1.
Nothing major here just lots of little changes for new hardware and
features. Highlights are:
- more USB 4 support added to the thunderbolt core
- build warning fixes all over the place
- usb-serial driver updates and new device support
- mtu3 driver updates
- gadget driver updates
- dwc3 driver updates
- dwc2 driver updates
- isp1760 host driver updates
- musb driver updates
- lots of other tiny things.
Full details are in the shortlog.
All of these have been in linux-next for a while now with no reported
issues"
* tag 'usb-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (223 commits)
phy: qcom-qusb2: Add configuration for SM4250 and SM6115
dt-bindings: phy: qcom,qusb2: document sm4250/6115 compatible
dt-bindings: usb: qcom,dwc3: Add bindings for sm6115/4250
USB: cdc-acm: blacklist Heimann USB Appset device
usb: xhci-mtk: allow multiple Start-Split in a microframe
usb: ftdi-elan: remove redundant continue statement in a while-loop
usb: class: cdc-wdm: return the correct errno code
xhci: remove redundant continue statement
usb: dwc3: Fix debugfs creation flow
usb: gadget: hid: fix error return code in hid_bind()
usb: gadget: eem: fix echo command packet response issue
usb: gadget: f_hid: fix endianness issue with descriptors
Revert "USB: misc: Add onboard_usb_hub driver"
Revert "of/platform: Add stubs for of_platform_device_create/destroy()"
Revert "usb: host: xhci-plat: Create platform device for onboard hubs in probe()"
Revert "arm64: dts: qcom: sc7180-trogdor: Add nodes for onboard USB hub"
xhci: solve a double free problem while doing s4
xhci: handle failed buffer copy to URB sg list and fix a W=1 copiler warning
xhci: Add adaptive interrupt rate for isoch TRBs with XHCI_AVOID_BEI quirk
xhci: Remove unused defines for ERST_SIZE and ERST_ENTRIES
...