vDSO VMA address is saved in mm_context for the purpose of using
restorer from vDSO page to return to userspace after signal handling.
In Checkpoint Restore in Userspace (CRIU) project we place vDSO VMA
on restore back to the place where it was on the dump.
Make vDSO code track the VMA address by supplying .mremap() fops
the same way it's done for x86 and arm by:
commit b059a453b1 ("x86/vdso: Add mremap hook to vm_special_mapping")
commit 739586951b ("arm64/vdso: Support mremap() for vDSO").
Signed-off-by: Guoyun Sun <sunguoyun@loongson.cn>
Signed-off-by: Paul Burton <paulburton@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Allison Randal <allison@lohutok.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Commit 716850ab10 ("MIPS: eBPF: Initial eBPF support for MIPS32
architecture.") enabled our eBPF JIT for MIPS32 kernels, whereas it has
previously only been availailable for MIPS64. It was my understanding at
the time that the BPF test suite was passing & JITing a comparable
number of tests to our cBPF JIT [1], but it turns out that was not the
case.
The eBPF JIT has a number of problems on MIPS32:
- Most notably various code paths still result in emission of MIPS64
instructions which will cause reserved instruction exceptions & kernel
panics when run on MIPS32 CPUs.
- The eBPF JIT doesn't account for differences between the O32 ABI used
by MIPS32 kernels versus the N64 ABI used by MIPS64 kernels. Notably
arguments beyond the first 4 are passed on the stack in O32, and this
is entirely unhandled when JITing a BPF_CALL instruction. Stack space
must be reserved for arguments even if they all fit in registers, and
the callee is free to assume that stack space has been reserved for
its use - with the eBPF JIT this is not the case, so calling any
function can result in clobbering values on the stack & unpredictable
behaviour. Function arguments in eBPF are always 64-bit values which
is also entirely unhandled - the JIT still uses a single (32-bit)
register per argument. As a result all function arguments are always
passed incorrectly when JITing a BPF_CALL instruction, leading to
kernel crashes or strange behavior.
- The JIT attempts to bail our on use of ALU64 instructions or 64-bit
memory access instructions. The code doing this at the start of
build_one_insn() incorrectly checks whether BPF_OP() equals BPF_DW,
when it should really be checking BPF_SIZE() & only doing so when
BPF_CLASS() is one of BPF_{LD,LDX,ST,STX}. This results in false
positives that cause more bailouts than intended, and that in turns
hides some of the problems described above.
- The kernel's cBPF->eBPF translation makes heavy use of 64-bit eBPF
instructions that the MIPS32 eBPF JIT bails out on, leading to most
cBPF programs not being JITed at all.
Until these problems are resolved, revert the removal of the cBPF JIT
performed by commit 716850ab10 ("MIPS: eBPF: Initial eBPF support for
MIPS32 architecture."). Together with commit f8fffebdea ("MIPS: BPF:
Disable MIPS32 eBPF JIT") this restores MIPS32 BPF JIT behavior back to
the same state it was prior to the introduction of the broken eBPF JIT
support.
[1] https://lore.kernel.org/linux-mips/MWHPR2201MB13583388481F01A422CE7D66D4410@MWHPR2201MB1358.namprd22.prod.outlook.com/
Signed-off-by: Paul Burton <paulburton@kernel.org>
Fixes: 716850ab10 ("MIPS: eBPF: Initial eBPF support for MIPS32 architecture.")
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Hassan Naveed <hnaveed@wavecomp.com>
Cc: Tony Ambardar <itugrok@yahoo.com>
Cc: bpf@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
1.Add X1830 system type for cat /proc/cpuinfo to give out X1830.
2.Change "PRID_IMP_XBURST" to "PRID_IMP_XBURST_REV1" and add a
new "PRID_IMP_XBURST_REV2" for new Ingenic CPUs which has
XBurst with MXU2 SIMD ISA.
Notice:
1."PRID_IMP_XBURST_REV2" is corresponds to the latest XBurst
processor with 128bit MXU2 SIMD instruction set, not the upcoming
XBurst2 processor. This version of the processors fixes issues
such as BTB and HPTLB.
2.In order to simplify and reuse the code, the "c->cputype" and
the "c->writecombine" and the "__cpu_name[cpu]" in the original
"PRID_IMP_XBURST" (now is "PRID_IMP_XBURST_REV1") are removed,
and the corresponding settings are abtained through fall-through
to "PRID_IMP_XBURST_REV2", which will cause the name that was
previously mistakenly called "JZRISC" to become to the real name
"XBurst".
Signed-off-by: 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>
Signed-off-by: Paul Burton <paulburton@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: yamada.masahiro@socionext.com
Cc: tglx@linutronix.de
Cc: chenhc@lemote.com
Cc: tbogendoerfer@suse.de
Cc: paul.burton@mips.com
Cc: paul@crapouillou.net
Cc: jhogan@kernel.org
Cc: fancer.lancer@gmail.com
Cc: ralf@linux-mips.org
Cc: jiaxun.yang@flygoat.com
Pull RISC-V fixes from Paul Walmsley:
"Several fixes for RISC-V:
- Fix function graph trace support
- Prefix the CSR IRQ_* macro names with "RV_", to avoid collisions
with macros elsewhere in the Linux kernel tree named "IRQ_TIMER"
- Use __pa_symbol() when computing the physical address of a kernel
symbol, rather than __pa()
- Mark the RISC-V port as supporting GCOV
One DT addition:
- Describe the L2 cache controller in the FU540 DT file
One documentation update:
- Add patch acceptance guideline documentation"
* tag 'riscv/for-v5.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
Documentation: riscv: add patch acceptance guidelines
riscv: prefix IRQ_ macro names with an RV_ namespace
clocksource: riscv: add notrace to riscv_sched_clock
riscv: ftrace: correct the condition logic in function graph tracer
riscv: dts: Add DT support for SiFive L2 cache controller
riscv: gcov: enable gcov for RISC-V
riscv: mm: use __pa_symbol for kernel symbols
Formalize, in kernel documentation, the patch acceptance policy for
arch/riscv. In summary, it states that as maintainers, we plan to
only accept patches for new modules or extensions that have been
frozen or ratified by the RISC-V Foundation.
We've been following these guidelines for the past few months. In the
meantime, we've received quite a bit of feedback that it would be
helpful to have these guidelines formally documented.
Based on a suggestion from Matthew Wilcox, we also add a link to this
file to Documentation/process/index.rst, to make this document easier
to find. The format of this document has also been changed to align
to the format outlined in the maintainer entry profiles, in accordance
with comments from Jon Corbet and Dan Williams.
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Krste Asanovic <krste@berkeley.edu>
Cc: Andrew Waterman <waterman@eecs.berkeley.edu>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jonathan Corbet <corbet@lwn.net>
"IRQ_TIMER", used in the arch/riscv CSR header file, is a sufficiently
generic macro name that it's used by several source files across the
Linux code base. Some of these other files ultimately include the
arch/riscv CSR include file, causing collisions. Fix by prefixing the
RISC-V csr.h IRQ_ macro names with an RV_ prefix.
Fixes: a4c3733d32 ("riscv: abstract out CSR names for supervisor vs machine mode")
Reported-by: Olof Johansson <olof@lixom.net>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Merge misc fixes from Andrew Morton:
"17 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
hexagon: define ioremap_uc
ocfs2: fix the crash due to call ocfs2_get_dlm_debug once less
ocfs2: call journal flush to mark journal as empty after journal recovery when mount
mm/hugetlb: defer freeing of huge pages if in non-task context
mm/gup: fix memory leak in __gup_benchmark_ioctl
mm/oom: fix pgtables units mismatch in Killed process message
fs/posix_acl.c: fix kernel-doc warnings
hexagon: work around compiler crash
hexagon: parenthesize registers in asm predicates
fs/namespace.c: make to_mnt_ns() static
fs/nsfs.c: include headers for missing declarations
fs/direct-io.c: include fs/internal.h for missing prototype
mm: move_pages: return valid node id in status if the page is already on the target node
memcg: account security cred as well to kmemcg
kcov: fix struct layout for kcov_remote_arg
mm/zsmalloc.c: fix the migrated zspage statistics.
mm/memory_hotplug: shrink zones when offlining memory
Pull apparmor fixes from John Johansen:
- performance regression: only get a label reference if the fast path
check fails
- fix aa_xattrs_match() may sleep while holding a RCU lock
- fix bind mounts aborting with -ENOMEM
* tag 'apparmor-pr-2020-01-04' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor:
apparmor: fix aa_xattrs_match() may sleep while holding a RCU lock
apparmor: only get a label reference if the fast path check fails
apparmor: fix bind mounts aborting with -ENOMEM
aa_xattrs_match() is unfortunately calling vfs_getxattr_alloc() from a
context protected by an rcu_read_lock. This can not be done as
vfs_getxattr_alloc() may sleep regardles of the gfp_t value being
passed to it.
Fix this by breaking the rcu_read_lock on the policy search when the
xattr match feature is requested and restarting the search if a policy
changes occur.
Fixes: 8e51f9087f ("apparmor: Add support for attaching profiles via xattr, presence and value")
Reported-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Pull MIPS fixes from Paul Burton:
"A collection of MIPS fixes:
- Fill the struct cacheinfo shared_cpu_map field with sensible
values, notably avoiding issues with perf which was unhappy in the
absence of these values.
- A boot fix for Loongson 2E & 2F machines which was fallout from
some refactoring performed this cycle.
- A Kconfig dependency fix for the Loongson CPU HWMon driver.
- A couple of VDSO fixes, ensuring gettimeofday() behaves
appropriately for kernel configurations that don't include support
for a clocksource the VDSO can use & fixing the calling convention
for the n32 & n64 VDSOs which would previously clobber the $gp/$28
register.
- A build fix for vmlinuz compressed images which were
inappropriately building with -fsanitize-coverage despite not being
part of the kernel proper, then failing to link due to the missing
__sanitizer_cov_trace_pc() function.
- A couple of eBPF JIT fixes, including disabling it for MIPS32 due
to a large number of issues with the code generated there &
reflecting ISA dependencies in Kconfig to enforce that systems
which don't support the JIT must include the interpreter"
* tag 'mips_fixes_5.5_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
MIPS: Avoid VDSO ABI breakage due to global register variable
MIPS: BPF: eBPF JIT: check for MIPS ISA compliance in Kconfig
MIPS: BPF: Disable MIPS32 eBPF JIT
MIPS: Prevent link failure with kcov instrumentation
MIPS: Kconfig: Use correct form for 'depends on'
mips: Fix gettimeofday() in the vdso library
MIPS: Fix boot on Fuloong2 systems
mips: cacheinfo: report shared CPU map
