Linux kernel
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The CPU hotplug support has been tested on QEMU, Spike, and SiFive
Unleashed so let's enable it by default in RV32 and RV64 defconfigs.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
In theory these are orthogonal, but in practice all NUMA systems are
SMP. NUMA && !SMP doesn't build, everyone else is coupling them, and I
don't really see any value in supporting that configuration.
Fixes: 4f0e8eef772e ("riscv: Add numa support for riscv64 platform")
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Suggested-by: Atish Patra <atishp@atishpatra.org>
Reported-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Tested-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Pull RISC-V updates from Palmer Dabbelt:
"A handful of new RISC-V related patches for this merge window:
- A check to ensure drivers are properly using uaccess. This isn't
manifesting with any of the drivers I'm currently using, but may
catch errors in new drivers.
- Some preliminary support for the FU740, along with the HiFive
Unleashed it will appear on.
- NUMA support for RISC-V, which involves making the arm64 code
generic.
- Support for kasan on the vmalloc region.
- A handful of new drivers for the Kendryte K210, along with the DT
plumbing required to boot on a handful of K210-based boards.
- Support for allocating ASIDs.
- Preliminary support for kernels larger than 128MiB.
- Various other improvements to our KASAN support, including the
utilization of huge pages when allocating the KASAN regions.
We may have already found a bug with the KASAN_VMALLOC code, but it's
passing my tests. There's a fix in the works, but that will probably
miss the merge window.
* tag 'riscv-for-linus-5.12-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (75 commits)
riscv: Improve kasan population by using hugepages when possible
riscv: Improve kasan population function
riscv: Use KASAN_SHADOW_INIT define for kasan memory initialization
riscv: Improve kasan definitions
riscv: Get rid of MAX_EARLY_MAPPING_SIZE
soc: canaan: Sort the Makefile alphabetically
riscv: Disable KSAN_SANITIZE for vDSO
riscv: Remove unnecessary declaration
riscv: Add Canaan Kendryte K210 SD card defconfig
riscv: Update Canaan Kendryte K210 defconfig
riscv: Add Kendryte KD233 board device tree
riscv: Add SiPeed MAIXDUINO board device tree
riscv: Add SiPeed MAIX GO board device tree
riscv: Add SiPeed MAIX DOCK board device tree
riscv: Add SiPeed MAIX BiT board device tree
riscv: Update Canaan Kendryte K210 device tree
dt-bindings: add resets property to dw-apb-timer
dt-bindings: fix sifive gpio properties
dt-bindings: update sifive uart compatible string
dt-bindings: update sifive clint compatible string
...
Pull arm64 fixes from Will Deacon:
"The big one is a fix for the VHE enabling path during early boot,
where the code enabling the MMU wasn't necessarily in the identity map
of the new page-tables, resulting in a consistent crash with 64k
pages. In fixing that, we noticed some missing barriers too, so we
added those for the sake of architectural compliance.
Other than that, just the usual merge window trickle. There'll be more
to come, too.
Summary:
- Fix lockdep false alarm on resume-from-cpuidle path
- Fix memory leak in kexec_file
- Fix module linker script to work with GDB
- Fix error code when trying to use uprobes with AArch32 instructions
- Fix late VHE enabling with 64k pages
- Add missing ISBs after TLB invalidation
- Fix seccomp when tracing syscall -1
- Fix stacktrace return code at end of stack
- Fix inconsistent whitespace for pointer return values
- Fix compiler warnings when building with W=1"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: stacktrace: Report when we reach the end of the stack
arm64: ptrace: Fix seccomp of traced syscall -1 (NO_SYSCALL)
arm64: Add missing ISB after invalidating TLB in enter_vhe
arm64: Add missing ISB after invalidating TLB in __primary_switch
arm64: VHE: Enable EL2 MMU from the idmap
KVM: arm64: make the hyp vector table entries local
arm64/mm: Fixed some coding style issues
arm64: uprobe: Return EOPNOTSUPP for AARCH32 instruction probing
kexec: move machine_kexec_post_load() to public interface
arm64 module: set plt* section addresses to 0x0
arm64: kexec_file: fix memory leakage in create_dtb() when fdt_open_into() fails
arm64: spectre: Prevent lockdep splat on v4 mitigation enable path
The kasan functions that populates the shadow regions used to allocate them
page by page and did not take advantage of hugepages, so fix this by
trying to allocate hugepages of 1GB and fallback to 2MB hugepages or 4K
pages in case it fails.
This reduces the page table memory consumption and improves TLB usage,
as shown below:
Before this patch:
---[ Kasan shadow start ]---
0xffffffc000000000-0xffffffc400000000 0x00000000818ef000 16G PTE . A . . . . R V
0xffffffc400000000-0xffffffc447fc0000 0x00000002b7f4f000 1179392K PTE D A . . . W R V
0xffffffc480000000-0xffffffc800000000 0x00000000818ef000 14G PTE . A . . . . R V
---[ Kasan shadow end ]---
After this patch:
---[ Kasan shadow start ]---
0xffffffc000000000-0xffffffc400000000 0x00000000818ef000 16G PTE . A . . . . R V
0xffffffc400000000-0xffffffc440000000 0x0000000240000000 1G PGD D A . . . W R V
0xffffffc440000000-0xffffffc447e00000 0x00000002b7e00000 126M PMD D A . . . W R V
0xffffffc447e00000-0xffffffc447fc0000 0x00000002b818f000 1792K PTE D A . . . W R V
0xffffffc480000000-0xffffffc800000000 0x00000000818ef000 14G PTE . A . . . . R V
---[ Kasan shadow end ]---
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Pull m68knommu update from Greg Ungerer:
"Only a single change. NULL parameter check in the local ColdFire
clocking code"
* tag 'm68knommu-for-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
m68k: let clk_enable() return immediately if clk is NULL
Currently the arm64 unwinder code returns -EINVAL whenever it can't find
the next stack frame, not distinguishing between cases where the stack has
been corrupted or is otherwise in a state it shouldn't be and cases
where we have reached the end of the stack. At the minute none of the
callers care what error code is returned but this will be important for
reliable stack trace which needs to be sure that the stack is intact.
Change to return -ENOENT in the case where we reach the bottom of the
stack. The error codes from this function are only used in kernel, this
particular code is chosen as we are indicating that we know there is no
frame there.
Signed-off-by: Mark Brown <broonie@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20210224165037.24138-1-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Current population code populates a whole page table without taking care
of what could have been already allocated and without taking into account
possible index in page table, assuming the virtual address to map is always
aligned on the page table size, which, for example, won't be the case when
the kernel will get pushed to the end of the address space.
Address those problems by rewriting the kasan population function,
splitting it into subfunctions for each different page table level.
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Pull tracing fixes from Steven Rostedt:
"Two fixes:
- Fix an unsafe printf string usage in a kmem trace event
- Fix spelling in output from the latency-collector tool"
* tag 'trace-v5.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing/tools: fix a couple of spelling mistakes
mm, tracing: Fix kmem_cache_free trace event to not print stale pointers
Similar to commit<742859adc721>("m68k: let clk_disable() return immediately if clk is NULL").
there should be a check for clk to prevent NULL pointer dereference.
Signed-off-by: Defang Bo <bodefang@126.com>
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
Since commit f086f67485c5 ("arm64: ptrace: add support for syscall
emulation"), if system call number -1 is called and the process is being
traced with PTRACE_SYSCALL, for example by strace, the seccomp check is
skipped and -ENOSYS is returned unconditionally (unless altered by the
tracer) rather than carrying out action specified in the seccomp filter.
The consequence of this is that it is not possible to reliably strace
a seccomp based implementation of a foreign system call interface in
which r7/x8 is permitted to be -1 on entry to a system call.
Also trace_sys_enter and audit_syscall_entry are skipped if a system
call is skipped.
Fix by removing the in_syscall(regs) check restoring the previous
behaviour which is like AArch32, x86 (which uses generic code) and
everything else.
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Catalin Marinas<catalin.marinas@arm.com>
Cc: <stable@vger.kernel.org>
Fixes: f086f67485c5 ("arm64: ptrace: add support for syscall emulation")
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Timothy E Baldwin <T.E.Baldwin99@members.leeds.ac.uk>
Link: https://lore.kernel.org/r/90edd33b-6353-1228-791f-0336d94d5f8c@majoroak.me.uk
Signed-off-by: Will Deacon <will@kernel.org>
Instead of hardcoding memory initialization to 0, use KASAN_SHADOW_INIT.
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Pull orphan handling fix from Kees Cook:
"Another case of bogus .eh_frame emission was noticed under
CONFIG_GCOV_KERNEL=y.
Summary:
- Define SANITIZER_DISCARDS with CONFIG_GCOV_KERNEL=y (Nathan
Chancellor)"
* tag 'orphan-handling-v5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
vmlinux.lds.h: Define SANITIZER_DISCARDS with CONFIG_GCOV_KERNEL=y