Attempt to mount 9p file system as root gives the following kernel panic:
9pnet_virtio: no channels available for device root
Kernel panic - not syncing: VFS: Unable to mount root "root" (9p), err=-2
CPU: 2 PID: 1 Comm: swapper/0 Not tainted 5.15.0-rc1+ #127
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
Call Trace:
dump_stack_lvl+0x45/0x59
panic+0x1e2/0x44b
? __warn_printk+0xf3/0xf3
? free_unref_page+0x2d4/0x4a0
? trace_hardirqs_on+0x32/0x120
? free_unref_page+0x2d4/0x4a0
mount_root+0x189/0x1e0
prepare_namespace+0x136/0x165
kernel_init_freeable+0x3b8/0x3cb
? rest_init+0x2e0/0x2e0
kernel_init+0x19/0x130
ret_from_fork+0x1f/0x30
Kernel Offset: disabled
---[ end Kernel panic - not syncing: VFS: Unable to mount root "root" (9p), err=-2 ]---
QEMU command line:
"qemu-system-x86_64 -append root=/dev/root rw rootfstype=9p rootflags=trans=virtio ..."
This error is because root_device_name is truncated in prepare_namespace() from
being "/dev/root" to be "root" prior to call to mount_nodev_root().
As a solution, don't treat errors in mount_nodev_root() as errors that
require panics and allow failback to the mount flow that existed before
patch citied in Fixes tag.
Fixes: f9259be6a9 ("init: allow mounting arbitrary non-blockdevice filesystems as root")
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
split_fs_names() currently takes comma separate list of filesystems
and converts it into individual filesystem strings. Pleaces these
strings in the input buffer passed by caller and returns number of
strings.
If caller manages to pass input string bigger than buffer, then we
can write beyond the buffer. Or if string just fits buffer, we will
still write beyond the buffer as we append a '\0' byte at the end.
Pass size of input buffer to split_fs_names() and put enough checks
in place so such buffer overrun possibilities do not occur.
This patch does few things.
- Add a parameter "size" to split_fs_names(). This specifies size
of input buffer.
- Use strlcpy() (instead of strcpy()) so that we can't go beyond
buffer size. If input string "names" is larger than passed in
buffer, input string will be truncated to fit in buffer.
- Stop appending extra '\0' character at the end and avoid one
possibility of going beyond the input buffer size.
- Do not use extra loop to count number of strings.
- Previously if one passed "rootfstype=foo,,bar", split_fs_names()
will return only 1 string "foo" (and "bar" will be truncated
due to extra ,). After this patch, now split_fs_names() will
return 3 strings ("foo", zero-sized-string, and "bar").
Callers of split_fs_names() have been modified to check for
zero sized string and skip to next one.
Reported-by: xu xin <xu.xin16@zte.com.cn>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Nathan Chancellor reports that the recent change to pci_iounmap in
commit 9caea00076 ("parisc: Declare pci_iounmap() parisc version only
when CONFIG_PCI enabled") causes build errors on arm64.
It took me about two hours to convince myself that I think I know what
the logic of that mess of #ifdef's in the <asm-generic/io.h> header file
really aim to do, and rewrite it to be easier to follow.
Famous last words.
Anyway, the code has now been lifted from that grotty header file into
lib/pci_iomap.c, and has fairly extensive comments about what the logic
is. It also avoids indirecting through another confusing (and badly
named) helper function that has other preprocessor config conditionals.
Let's see what odd architecture did something else strange in this area
to break things. But my arm64 cross build is clean.
Fixes: 9caea00076 ("parisc: Declare pci_iounmap() parisc version only when CONFIG_PCI enabled")
Reported-by: Nathan Chancellor <nathan@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Ulrich Teichert <krypton@ulrich-teichert.org>
Cc: James Bottomley <James.Bottomley@hansenpartnership.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull x86 fixes from Borislav Petkov:
- Prevent a infinite loop in the MCE recovery on return to user space,
which was caused by a second MCE queueing work for the same page and
thereby creating a circular work list.
- Make kern_addr_valid() handle existing PMD entries, which are marked
not present in the higher level page table, correctly instead of
blindly dereferencing them.
- Pass a valid address to sanitize_phys(). This was caused by the
mixture of inclusive and exclusive ranges. memtype_reserve() expect
'end' being exclusive, but sanitize_phys() wants it inclusive. This
worked so far, but with end being the end of the physical address
space the fail is exposed.
- Increase the maximum supported GPIO numbers for 64bit. Newer SoCs
exceed the previous maximum.
* tag 'x86_urgent_for_v5.15_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mce: Avoid infinite loop for copy from user recovery
x86/mm: Fix kern_addr_valid() to cope with existing but not present entries
x86/platform: Increase maximum GPIO number for X86_64
x86/pat: Pass valid address to sanitize_phys()
Pull perf event fix from Thomas Gleixner:
"A single fix for the perf core where a value read with READ_ONCE() was
checked and then reread which makes all the checks invalid. Reuse the
already read value instead"
* tag 'perf-urgent-2021-09-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
events: Reuse value read using READ_ONCE instead of re-reading it
Pull locking fixes from Thomas Gleixner:
"A set of updates for the RT specific reader/writer locking base code:
- Make the fast path reader ordering guarantees correct.
- Code reshuffling to make the fix simpler"
[ This plays ugly games with atomic_add_return_release() because we
don't have a plain atomic_add_release(), and should really be cleaned
up, I think - Linus ]
* tag 'locking-urgent-2021-09-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/rwbase: Take care of ordering guarantee for fastpath reader
locking/rwbase: Extract __rwbase_write_trylock()
locking/rwbase: Properly match set_and_save_state() to restore_state()
Pull powerpc fixes from Michael Ellerman:
- Fix crashes when scv (System Call Vectored) is used to make a syscall
when a transaction is active, on Power9 or later.
- Fix bad interactions between rfscv (Return-from scv) and Power9
fake-suspend mode.
- Fix crashes when handling machine checks in LPARs using the Hash MMU.
- Partly revert a recent change to our XICS interrupt controller code,
which broke the recently added Microwatt support.
Thanks to Cédric Le Goater, Eirik Fuller, Ganesh Goudar, Gustavo Romero,
Joel Stanley, Nicholas Piggin.
* tag 'powerpc-5.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/xics: Set the IRQ chip data for the ICS native backend
powerpc/mce: Fix access error in mce handler
KVM: PPC: Book3S HV: Tolerate treclaim. in fake-suspend mode changing registers
powerpc/64s: system call rfscv workaround for TM bugs
selftests/powerpc: Add scv versions of the basic TM syscall tests
powerpc/64s: system call scv tabort fix for corrupt irq soft-mask state
Pull Kbuild fixes from Masahiro Yamada:
- Fix bugs in checkkconfigsymbols.py
- Fix missing sys import in gen_compile_commands.py
- Fix missing FORCE warning for ARCH=sh builds
- Fix -Wignored-optimization-argument warnings for Clang builds
- Turn -Wignored-optimization-argument into an error in order to stop
building instead of sprinkling warnings
* tag 'kbuild-fixes-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kbuild: Add -Werror=ignored-optimization-argument to CLANG_FLAGS
x86/build: Do not add -falign flags unconditionally for clang
kbuild: Fix comment typo in scripts/Makefile.modpost
sh: Add missing FORCE prerequisites in Makefile
gen_compile_commands: fix missing 'sys' package
checkkconfigsymbols.py: Remove skipping of help lines in parse_kconfig_file
checkkconfigsymbols.py: Forbid passing 'HEAD' to --commit
Pull perf tools fixes from Arnaldo Carvalho de Melo:
- Fix ip display in 'perf script' when output type != attr->type.
- Ignore deprecation warning when using libbpf'sg btf__get_from_id(),
fixing the build with libbpf v0.6+.
- Make use of FD() robust in libperf, fixing a segfault with 'perf stat
--iostat list'.
- Initialize addr_location:srcline pointer to NULL when resolving
callchain addresses.
- Fix fused instruction logic for assembly functions in 'perf
annotate'.
* tag 'perf-tools-fixes-for-v5.15-2021-09-18' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
perf bpf: Ignore deprecation warning when using libbpf's btf__get_from_id()
libperf evsel: Make use of FD robust.
perf machine: Initialize srcline string member in add_location struct
perf script: Fix ip display when type != attr->type
perf annotate: Fix fused instr logic for assembly functions
The old dmascc driver depends on the legacy ISA_DMA_API, and blindly
just casts the kernel virtual address to 'int' for set_dma_addr().
That works only incidentally, and because the high bits of the address
will be ignored anyway. And on 64-bit architectures it causes warnings.
Admittedly, 64-bit architectures with ISA are basically dead - I think
the only example of this is alpha, and nobody would ever use the dmascc
driver there. But hey, the fix is easy enough, the end result is
cleaner, and it's yet another configuration that now builds without
warnings.
If somebody actually uses this driver on an alpha and this fixes it for
you, please email me. Because that is just incredibly bizarre.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With the previous commit (9caea00076: "parisc: Declare pci_iounmap()
parisc version only when CONFIG_PCI enabled") we can now enable
GENERIC_PCI_IOMAP unconditionally on alpha, and if PCI is not enabled we
will just get the nice empty helper functions that allow mixed-bus
drivers to build.
Example driver: the old 3com/3c59x.c driver works with either the PCI or
the EISA version of the 3x59x card, but wouldn't build in an EISA-only
configuration because of missing pci_iomap() and pci_iounmap() dummy
wrappers.
Most of the other PCI infrastructure just becomes empty wrappers even
without GENERIC_PCI_IOMAP, and it's not obvious that the pci_iomap
functionality shouldn't do the same, but this works.
Cc: Ulrich Teichert <krypton@ulrich-teichert.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Similar to commit 589834b3a0 ("kbuild: Add
-Werror=unknown-warning-option to CLANG_FLAGS").
Clang ignores certain GCC flags that it has not implemented, only
emitting a warning:
$ echo | clang -fsyntax-only -falign-jumps -x c -
clang-14: warning: optimization flag '-falign-jumps' is not supported
[-Wignored-optimization-argument]
When one of these flags gets added to KBUILD_CFLAGS unconditionally, all
subsequent cc-{disable-warning,option} calls fail because -Werror was
added to these invocations to turn the above warning and the equivalent
-W flag warning into errors.
To catch the presence of these flags earlier, turn
-Wignored-optimization-argument into an error so that the flags can
either be implemented or ignored via cc-option and there are no more
weird errors.
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
clang does not support -falign-jumps and only recently gained support
for -falign-loops. When one of the configuration options that adds these
flags is enabled, clang warns and all cc-{disable-warning,option} that
follow fail because -Werror gets added to test for the presence of this
warning:
clang-14: warning: optimization flag '-falign-jumps=0' is not supported
[-Wignored-optimization-argument]
To resolve this, add a couple of cc-option calls when building with
clang; gcc has supported these options since 3.2 so there is no point in
testing for their support. -falign-functions was implemented in clang-7,
-falign-loops was implemented in clang-14, and -falign-jumps has not
been implemented yet.
Link: https://lore.kernel.org/r/YSQE2f5teuvKLkON@Ryzen-9-3900X.localdomain/
Link: https://lore.kernel.org/r/20210824022640.2170859-2-nathan@kernel.org/
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Change comment "create one <module>.mod.c file pr. module"
to "create one <module>.mod.c file per module"
Signed-off-by: Ramji Jiyani <ramjiyani@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
make:
arch/sh/boot/Makefile:87: FORCE prerequisite is missing
Add the missing FORCE prerequisites for all build targets identified by
"make help".
Fixes: e1f86d7b4b ("kbuild: warn if FORCE is missing for if_changed(_dep,_rule) and filechk")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
We need to import the 'sys' package since the script has called
sys.exit() method.
Fixes: 6ad7cbc015 ("Makefile: Add clang-tidy and static analyzer support to makefile")
Signed-off-by: Kortan <kortanzh@gmail.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
When parsing Kconfig files to find symbol definitions and references,
lines after a 'help' line are skipped until a new config definition
starts.
However, Kconfig statements can actually be after a help section, as
long as these have shallower indentation. These are skipped by the
parser.
This means that symbols referenced in this kind of statements are
ignored by this function and thus are not considered undefined
references in case the symbol is not defined.
Remove the 'skip' logic entirely, as it is not needed if we just use the
STMT regex to find the end of help lines.
However, this means that keywords that appear as part of the help
message (i.e. with the same indentation as the help lines) it will be
considered as a reference/definition. This can happen now as well, but
only with REGEX_KCONFIG_DEF lines. Also, the keyword must have a SYMBOL
after it, which probably means that someone referenced a config in the
help so it seems like a bonus :)
The real solution is to keep track of the indentation when a the first
help line in encountered and then handle DEF and STMT lines only if the
indentation is shallower.
Signed-off-by: Ariel Marcovitch <arielmarcovitch@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
As opposed to the --diff option, --commit can get ref names instead of
commit hashes.
When using the --commit option, the script resets the working directory
to the commit before the given ref, by adding '~' to the end of the ref.
However, the 'HEAD' ref is relative, and so when the working directory
is reset to 'HEAD~', 'HEAD' points to what was 'HEAD~'. Then when the
script resets to 'HEAD' it actually stays in the same commit. In this
case, the script won't report any cases because there is no diff between
the cases of the two refs.
Prevent the user from using HEAD refs.
A better solution might be to resolve the refs before doing the
reset, but for now just disallow such refs.
Signed-off-by: Ariel Marcovitch <arielmarcovitch@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
We already had the implementation for __udiv_qrnnd (unsigned divide for
multi-precision arithmetic) as part of the alpha math emulation code.
But you can disable the math emulation code - even if you shouldn't -
and then the MPI code that actually wants this functionality (and is
needed by various crypto functions) will fail to build.
So move the extended-precision divide code to be a regular library
function, just like all the regular division code is. That way ie is
available regardless of math-emulation.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ok, it almost certainly is still broken on actual hardware, but the
immediate reason for it having been marked BROKEN was a build error that
is fixed by just making sure the low-level IO header file is included
sufficiently early that the __EXTERN_INLINE hackery takes effect.
This was marked broken back in 2017 by commit 1883c9f49d ("alpha: mark
jensen as broken"), but Ulrich Teichert made me look at it as part of my
cross-build work to make sure -Werror actually does the right thing.
There are lots of alpha configurations that do not build cleanly, but
now it's no longer because Jensen wouldn't be buildable. That said,
because the Jensen platform doesn't force PCI to be enabled (Jensen only
had EISA), it ends up being somewhat interesting as a source of odd
configs.
Reported-by: Ulrich Teichert <krypton@ulrich-teichert.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Perf code re-implements libbpf's btf__load_from_kernel_by_id() API as
a weak function, presumably to dynamically link against old version of
libbpf shared library. Unfortunately this causes compilation warning
when perf is compiled against libbpf v0.6+.
For now, just ignore deprecation warning, but there might be a better
solution, depending on perf's needs.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: kernel-team@fb.com
LPU-Reference: 20210914170004.4185659-1-andrii@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Leon Romanovsky
Vivek Goyal
Linus Torvalds
Helge Deller
Nathan Chancellor
Ramji Jiyani
Geert Uytterhoeven
Kortan
Ariel Marcovitch
Andrii Nakryiko