Pull RISC-V fixes from Palmer Dabbelt:
- A fix for the CMODX example in the recently added icache flushing
prctl()
- A fix to the perf driver to avoid corrupting event data on counter
overflows when external overflow handlers are in use
- A fix to clear all hardware performance monitor events on boot, to
avoid dangling events firmware or previously booted kernels from
triggering spuriously
- A fix to the perf event probing logic to avoid erroneously reporting
the presence of unimplemented counters. This also prevents some
implemented counters from being reported
- A build fix for the vector sigreturn selftest on clang
- A fix to ftrace, which now requires the previously optional index
argument to ftrace_graph_ret_addr()
- A fix to avoid deadlocking if kexec crash handling triggers in an
interrupt context
* tag 'riscv-for-linus-6.10-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: kexec: Avoid deadlock in kexec crash path
riscv: stacktrace: fix usage of ftrace_graph_ret_addr()
riscv: selftests: Fix vsetivli args for clang
perf: RISC-V: Check standard event availability
drivers/perf: riscv: Reset the counter to hpmevent mapping while starting cpus
drivers/perf: riscv: Do not update the event data if uptodate
documentation: Fix riscv cmodx example
ftrace_graph_ret_addr() takes an `idx` integer pointer that is used to
optimize the stack unwinding. Pass it a valid pointer to utilize the
optimizations that might be available in the future.
The commit is making riscv's usage of ftrace_graph_ret_addr() match
x86_64.
Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Link: https://lore.kernel.org/r/20240618145820.62112-1-puranjay@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Atish Patra <atishp@rivosinc.com> says:
This series contains 3 fixes out of which the first one is a new fix
for invalid event data reported in lkml[2]. The last two are v3 of Samuel's
patch[1]. I added the RB/TB/Fixes tag and moved 1 unrelated change
to its own patch. I also changed an error message in kvm vcpu_pmu from
pr_err to pr_debug to avoid redundant failure error messages generated
due to the boot time quering of events implemented in the patch[1]
Here is the original cover letter for the patch[1]
Before this patch:
$ perf list hw
List of pre-defined events (to be used in -e or -M):
branch-instructions OR branches [Hardware event]
branch-misses [Hardware event]
bus-cycles [Hardware event]
cache-misses [Hardware event]
cache-references [Hardware event]
cpu-cycles OR cycles [Hardware event]
instructions [Hardware event]
ref-cycles [Hardware event]
stalled-cycles-backend OR idle-cycles-backend [Hardware event]
stalled-cycles-frontend OR idle-cycles-frontend [Hardware event]
$ perf stat -ddd true
Performance counter stats for 'true':
4.36 msec task-clock # 0.744 CPUs utilized
1 context-switches # 229.325 /sec
0 cpu-migrations # 0.000 /sec
38 page-faults # 8.714 K/sec
4,375,694 cycles # 1.003 GHz (60.64%)
728,945 instructions # 0.17 insn per cycle
79,199 branches # 18.162 M/sec
17,709 branch-misses # 22.36% of all branches
181,734 L1-dcache-loads # 41.676 M/sec
5,547 L1-dcache-load-misses # 3.05% of all L1-dcache accesses
<not counted> LLC-loads (0.00%)
<not counted> LLC-load-misses (0.00%)
<not counted> L1-icache-loads (0.00%)
<not counted> L1-icache-load-misses (0.00%)
<not counted> dTLB-loads (0.00%)
<not counted> dTLB-load-misses (0.00%)
<not counted> iTLB-loads (0.00%)
<not counted> iTLB-load-misses (0.00%)
<not counted> L1-dcache-prefetches (0.00%)
<not counted> L1-dcache-prefetch-misses (0.00%)
0.005860375 seconds time elapsed
0.000000000 seconds user
0.010383000 seconds sys
After this patch:
$ perf list hw
List of pre-defined events (to be used in -e or -M):
branch-instructions OR branches [Hardware event]
branch-misses [Hardware event]
cache-misses [Hardware event]
cache-references [Hardware event]
cpu-cycles OR cycles [Hardware event]
instructions [Hardware event]
$ perf stat -ddd true
Performance counter stats for 'true':
5.16 msec task-clock # 0.848 CPUs utilized
1 context-switches # 193.817 /sec
0 cpu-migrations # 0.000 /sec
37 page-faults # 7.171 K/sec
5,183,625 cycles # 1.005 GHz
961,696 instructions # 0.19 insn per cycle
85,853 branches # 16.640 M/sec
20,462 branch-misses # 23.83% of all branches
243,545 L1-dcache-loads # 47.203 M/sec
5,974 L1-dcache-load-misses # 2.45% of all L1-dcache accesses
<not supported> LLC-loads
<not supported> LLC-load-misses
<not supported> L1-icache-loads
<not supported> L1-icache-load-misses
<not supported> dTLB-loads
19,619 dTLB-load-misses
<not supported> iTLB-loads
6,831 iTLB-load-misses
<not supported> L1-dcache-prefetches
<not supported> L1-dcache-prefetch-misses
0.006085625 seconds time elapsed
0.000000000 seconds user
0.013022000 seconds sys
[1] https://lore.kernel.org/linux-riscv/20240418014652.1143466-1-samuel.holland@sifive.com/
[2] https://lore.kernel.org/all/CC51D53B-846C-4D81-86FC-FBF969D0A0D6@pku.edu.cn/
* b4-shazam-merge:
perf: RISC-V: Check standard event availability
drivers/perf: riscv: Reset the counter to hpmevent mapping while starting cpus
drivers/perf: riscv: Do not update the event data if uptodate
Link: https://lore.kernel.org/r/20240628-misc_perf_fixes-v4-0-e01cfddcf035@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
The RISC-V SBI PMU specification defines several standard hardware and
cache events. Currently, all of these events are exposed to userspace,
even when not actually implemented. They appear in the `perf list`
output, and commands like `perf stat` try to use them.
This is more than just a cosmetic issue, because the PMU driver's .add
function fails for these events, which causes pmu_groups_sched_in() to
prematurely stop scheduling in other (possibly valid) hardware events.
Add logic to check which events are supported by the hardware (i.e. can
be mapped to some counter), so only usable events are reported to
userspace. Since the kernel does not know the mapping between events and
possible counters, this check must happen during boot, when no counters
are in use. Make the check asynchronous to minimize impact on boot time.
Fixes: e999143459 ("RISC-V: Add perf platform driver based on SBI PMU extension")
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Tested-by: Atish Patra <atishp@rivosinc.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Link: https://lore.kernel.org/r/20240628-misc_perf_fixes-v4-3-e01cfddcf035@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Pull SoC fixes from Arnd Bergmann:
"A number of devicetree fixes came in for the rockchip platforms,
correcting some of the address information, and reverting a change to
the MMC controller configuration that caused regressions.
Four drivers have one code change each, addressing minor build issues
for the optee firmware driver, the litex SoC platform driver and two
reset drivers.
The riscv fixes as also simple, mainly turning off device nodes in the
canaan dts files unless they are actually usable on a particular
board.
Finally, Drew takes over maintaining the THEAD RISC-V SoC platform"
* tag 'arm-fixes-6.10-2' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
drivers/soc/litex: drop obsolete dependency on COMPILE_TEST
tee: optee: ffa: Fix missing-field-initializers warning
arm64: dts: rockchip: Add sound-dai-cells for RK3368
arm64: dts: rockchip: Fix the i2c address of es8316 on Cool Pi 4B
reset: hisilicon: hi6220: add missing MODULE_DESCRIPTION() macro
reset: gpio: Fix missing gpiolib dependency for GPIO reset controller
MAINTAINERS: thead: update Maintainer
arm64: dts: rockchip: fix PMIC interrupt pin on ROCK Pi E
riscv: dts: starfive: Set EMMC vqmmc maximum voltage to 3.3V on JH7110 boards
arm64: dts: rockchip: make poweroff(8) work on Radxa ROCK 5A
Revert "arm64: dts: rockchip: remove redundant cd-gpios from rk3588 sdmmc nodes"
ARM: dts: rockchip: rk3066a: add #sound-dai-cells to hdmi node
arm64: dts: rockchip: Fix the value of `dlg,jack-det-rate` mismatch on rk3399-gru
arm64: dts: rockchip: set correct pwm0 pinctrl on rk3588-tiger
riscv: dts: canaan: Disable I/O devices unless used
riscv: dts: canaan: Clean up serial aliases
arm64: dts: rockchip: Rename LED related pinctrl nodes on rk3308-rock-pi-s
arm64: dts: rockchip: Fix SD NAND and eMMC init on rk3308-rock-pi-s
arm64: dts: rockchip: Fix rk3308 codec@ff560000 reset-names
arm64: dts: rockchip: Fix the DCDC_REG2 minimum voltage on Quartz64 Model B
Pull RISC-V fixes from Palmer Dabbelt:
- A fix for vector load/store instruction decoding, which could result
in reserved vector element length encodings decoding as valid vector
instructions.
- Instruction patching now aggressively flushes the local instruction
cache, to avoid situations where patching functions on the flush path
results in torn instructions being fetched.
- A fix to prevent the stack walker from showing up as part of traces.
* tag 'riscv-for-linus-6.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: stacktrace: convert arch_stack_walk() to noinstr
riscv: patch: Flush the icache right after patching to avoid illegal insns
RISC-V: fix vector insn load/store width mask
RISC-V Devicetree fixes for v6.10-rc5+
T-Head:
Jisheng hasn't got enough time to look after the platform, so Drew
Fustini is going to take over.
StarFive:
A fix for a regulator voltage range that prevented using low performance
SD cards.
Canaan:
Cleanup for some "over eager" aliases for serial ports that did not
exist on some boards and I/O devices disabled on boards where they were
not actually in use.
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
arch_stack_walk() is called intensively in function_graph when the
kernel is compiled with CONFIG_TRACE_IRQFLAGS. As a result, the kernel
logs a lot of arch_stack_walk and its sub-functions into the ftrace
buffer. However, these functions should not appear on the trace log
because they are part of the ftrace itself. This patch references what
arm64 does for the smae function. So it further prevent the re-enter
kprobe issue, which is also possible on riscv.
Related-to: commit 0fbcd8abf3 ("arm64: Prohibit instrumentation on arch_stack_walk()")
Fixes: 680341382d ("riscv: add CALLER_ADDRx support")
Signed-off-by: Andy Chiu <andy.chiu@sifive.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20240613-dev-andyc-dyn-ftrace-v4-v1-1-1a538e12c01e@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Most architectures that implement the old-style mmap() with byte offset
use 'unsigned long' as the type for that offset, but microblaze and
riscv have the off_t type that is shared with userspace, matching the
prototype in include/asm-generic/syscalls.h.
Make this consistent by using an unsigned argument everywhere. This
changes the behavior slightly, as the argument is shifted to a page
number, and an user input with the top bit set would result in a
negative page offset rather than a large one as we use elsewhere.
For riscv, the 32-bit sys_mmap2() definition actually used a custom
type that is different from the global declaration, but this was
missed due to an incorrect type check.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Currently, for JH7110 boards with EMMC slot, vqmmc voltage for EMMC is
fixed to 1.8V, while the spec needs it to be 3.3V on low speed mode and
should support switching to 1.8V when using higher speed mode. Since
there are no other peripherals using the same voltage source of EMMC's
vqmmc(ALDO4) on every board currently supported by mainline kernel,
regulator-max-microvolt of ALDO4 should be set to 3.3V.
Cc: stable@vger.kernel.org
Signed-off-by: Shengyu Qu <wiagn233@outlook.com>
Fixes: 7dafcfa79c ("riscv: dts: starfive: enable DCDC1&ALDO4 node in axp15060")
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Pull RISC-V fixes from Palmer Dabbelt:
- Another fix to avoid allocating pages that overlap with ERR_PTR,
which manifests on rv32
- A revert for the badaccess patch I incorrectly picked up an early
version of
* tag 'riscv-for-linus-6.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
Revert "riscv: mm: accelerate pagefault when badaccess"
riscv: fix overlap of allocated page and PTR_ERR
KVM/riscv fixes for 6.10, take #1
- No need to use mask when hart-index-bits is 0
- Fix incorrect reg_subtype labels in kvm_riscv_vcpu_set_reg_isa_ext()
When the maximum hart number within groups is 1, hart-index-bit is set to
0. Consequently, there is no need to restore the hart ID from IMSIC
addresses and hart-index-bit settings. Currently, QEMU and kvmtool do not
pass correct hart-index-bit values when the maximum hart number is a
power of 2, thereby avoiding this issue. Corresponding patches for QEMU
and kvmtool will also be dispatched.
Fixes: 89d01306e3 ("RISC-V: KVM: Implement device interface for AIA irqchip")
Signed-off-by: Yong-Xuan Wang <yongxuan.wang@sifive.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Link: https://lore.kernel.org/r/20240415064905.25184-1-yongxuan.wang@sifive.com
Signed-off-by: Anup Patel <anup@brainfault.org>
Top of the kernel thread stack should be reserved for pt_regs. However
this is not the case for the idle threads of the secondary boot harts.
Their stacks overlap with their pt_regs, so both may get corrupted.
Similar issue has been fixed for the primary hart, see c7cdd96eca
("riscv: prevent stack corruption by reserving task_pt_regs(p) early").
However that fix was not propagated to the secondary harts. The problem
has been noticed in some CPU hotplug tests with V enabled. The function
smp_callin stored several registers on stack, corrupting top of pt_regs
structure including status field. As a result, kernel attempted to save
or restore inexistent V context.
Fixes: 9a2451f186 ("RISC-V: Avoid using per cpu array for ordered booting")
Fixes: 2875fe0561 ("RISC-V: Add cpu_ops and modify default booting method")
Signed-off-by: Sergey Matyukevich <sergey.matyukevich@syntacore.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20240523084327.2013211-1-geomatsi@gmail.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
It is considered good practice to disable on-SoC devices providing
external I/O in the SoC-specific .dtsi, and enable them explicitly in
the board-specific DTS files when actually wired-up and used.
Hence:
- Set the status of I/O devices in k210.dtsi to "disabled",
- Override the status of used I/O devices in board-specific DTS files
to "okay",
- Drop unneeded status overrides in board DTS-specific files for the
always-enabled pin controller.
On e.g. MAiXBiT, this gets rid of an error message when probing the
unused slave-only spi2 controller:
dw_spi_mmio 50240000.spi: error -22: problem registering spi host
dw_spi_mmio 50240000.spi: probe with driver dw_spi_mmio failed with error -22
which is seen since commit 98d75b9ef2 ("spi: dw: Drop default
number of CS setting").
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
The SoC-specific k210.dtsi declares aliases for all four serial ports.
However, none of the board-specific DTS files configure pin control for
any but the first serial port, so the last three ports are not usable.
Move the aliases node from the SoC-specific k210.dtsi to the
board-specific DTS files, as these are really board-specific, and retain
the sole port that is usable.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Pull more RISC-V updates from Palmer Dabbelt:
- The compression format used for boot images is now configurable at
build time, and these formats are shown in `make help`
- access_ok() has been optimized
- A pair of performance bugs have been fixed in the uaccess handlers
- Various fixes and cleanups, including one for the IMSIC build failure
and one for the early-boot ftrace illegal NOPs bug
* tag 'riscv-for-linus-6.10-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: Fix early ftrace nop patching
irqchip: riscv-imsic: Fixup riscv_ipi_set_virq_range() conflict
riscv: selftests: Add signal handling vector tests
riscv: mm: accelerate pagefault when badaccess
riscv: uaccess: Relax the threshold for fast path
riscv: uaccess: Allow the last potential unrolled copy
riscv: typo in comment for get_f64_reg
Use bool value in set_cpu_online()
riscv: selftests: Add hwprobe binaries to .gitignore
riscv: stacktrace: fixed walk_stackframe()
ftrace: riscv: move from REGS to ARGS
riscv: do not select MODULE_SECTIONS by default
riscv: show help string for riscv-specific targets
riscv: make image compression configurable
riscv: cpufeature: Fix extension subset checking
riscv: cpufeature: Fix thead vector hwcap removal
riscv: rewrite __kernel_map_pages() to fix sleeping in invalid context
riscv: force PAGE_SIZE linear mapping if debug_pagealloc is enabled
riscv: Define TASK_SIZE_MAX for __access_ok()
riscv: Remove PGDIR_SIZE_L3 and TASK_SIZE_MIN
Commit c97bf62996 ("riscv: Fix text patching when IPI are used")
converted ftrace_make_nop() to use patch_insn_write() which does not
emit any icache flush relying entirely on __ftrace_modify_code() to do
that.
But we missed that ftrace_make_nop() was called very early directly when
converting mcount calls into nops (actually on riscv it converts 2B nops
emitted by the compiler into 4B nops).
This caused crashes on multiple HW as reported by Conor and Björn since
the booting core could have half-patched instructions in its icache
which would trigger an illegal instruction trap: fix this by emitting a
local flush icache when early patching nops.
Fixes: c97bf62996 ("riscv: Fix text patching when IPI are used")
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Reported-by: Conor Dooley <conor.dooley@microchip.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Björn Töpel <bjorn@rivosinc.com>
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Link: https://lore.kernel.org/r/20240523115134.70380-1-alexghiti@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Pull more non-mm updates from Andrew Morton:
- A series ("kbuild: enable more warnings by default") from Arnd
Bergmann which enables a number of additional build-time warnings. We
fixed all the fallout which we could find, there may still be a few
stragglers.
- Samuel Holland has developed the series "Unified cross-architecture
kernel-mode FPU API". This does a lot of consolidation of
per-architecture kernel-mode FPU usage and enables the use of newer
AMD GPUs on RISC-V.
- Tao Su has fixed some selftests build warnings in the series
"Selftests: Fix compilation warnings due to missing _GNU_SOURCE
definition".
- This pull also includes a nilfs2 fixup from Ryusuke Konishi.
* tag 'mm-nonmm-stable-2024-05-22-17-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (23 commits)
nilfs2: make block erasure safe in nilfs_finish_roll_forward()
selftests/harness: use 1024 in place of LINE_MAX
Revert "selftests/harness: remove use of LINE_MAX"
selftests/fpu: allow building on other architectures
selftests/fpu: move FP code to a separate translation unit
drm/amd/display: use ARCH_HAS_KERNEL_FPU_SUPPORT
drm/amd/display: only use hard-float, not altivec on powerpc
riscv: add support for kernel-mode FPU
x86: implement ARCH_HAS_KERNEL_FPU_SUPPORT
powerpc: implement ARCH_HAS_KERNEL_FPU_SUPPORT
LoongArch: implement ARCH_HAS_KERNEL_FPU_SUPPORT
lib/raid6: use CC_FLAGS_FPU for NEON CFLAGS
arm64: crypto: use CC_FLAGS_FPU for NEON CFLAGS
arm64: implement ARCH_HAS_KERNEL_FPU_SUPPORT
ARM: crypto: use CC_FLAGS_FPU for NEON CFLAGS
ARM: implement ARCH_HAS_KERNEL_FPU_SUPPORT
arch: add ARCH_HAS_KERNEL_FPU_SUPPORT
x86/fpu: fix asm/fpu/types.h include guard
kbuild: enable -Wcast-function-type-strict unconditionally
kbuild: enable -Wformat-truncation on clang
...
Charlie Jenkins <charlie@rivosinc.com> says:
This series contains two minor fixes for the extension parsing in
cpufeature.c.
Some T-Head boards without vector 1.0 support report "v" in the isa
string in their DT which will cause the kernel to run vector code. The
code to blacklist "v" from these boards was doing so by using
riscv_cached_mvendorid() which has not been populated at the time of
extension parsing. This fix instead greedily reads the mvendorid CSR of
the boot hart to determine if the cpu is from T-Head.
The other fix is for an incorrect indexing bug. riscv extensions
sometimes imply other extensions. When adding these "subset" extensions
to the hardware capabilities array, they need to be checked if they are
valid. The current code only checks if the extension that is including
other extensions is valid and not the subset extensions.
These patches were previously included in:
https://lore.kernel.org/lkml/20240420-dev-charlie-support_thead_vector_6_9-v3-0-67cff4271d1d@rivosinc.com/
* b4-shazam-merge:
riscv: cpufeature: Fix extension subset checking
riscv: cpufeature: Fix thead vector hwcap removal
Link: https://lore.kernel.org/r/20240502-cpufeature_fixes-v4-0-b3d1a088722d@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Nam Cao <namcao@linutronix.de> says:
The debug_pagealloc feature is not functional on RISCV. With this feature
enabled (CONFIG_DEBUG_PAGEALLOC=y and debug_pagealloc=on), kernel crashes
early during boot.
QEMU command that can reproduce this problem:
qemu-system-riscv64 -machine virt \
-kernel Image \
-append "console=ttyS0 root=/dev/vda debug_pagealloc=on" \
-nographic \
-drive "file=root.img,format=raw,id=hd0" \
-device virtio-blk-device,drive=hd0 \
-m 4G \
This series makes debug_pagealloc functional.
* b4-shazam-merge:
riscv: rewrite __kernel_map_pages() to fix sleeping in invalid context
riscv: force PAGE_SIZE linear mapping if debug_pagealloc is enabled
Link: https://lore.kernel.org/r/cover.1715750938.git.namcao@linutronix.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
If the load access fault occures in a leaf function (with
CONFIG_FRAME_POINTER=y), when wrong stack trace will be displayed:
[<ffffffff804853c2>] regmap_mmio_read32le+0xe/0x1c
---[ end trace 0000000000000000 ]---
Registers dump:
ra 0xffffffff80485758 <regmap_mmio_read+36>
sp 0xffffffc80200b9a0
fp 0xffffffc80200b9b0
pc 0xffffffff804853ba <regmap_mmio_read32le+6>
Stack dump:
0xffffffc80200b9a0: 0xffffffc80200b9e0 0xffffffc80200b9e0
0xffffffc80200b9b0: 0xffffffff8116d7e8 0x0000000000000100
0xffffffc80200b9c0: 0xffffffd8055b9400 0xffffffd8055b9400
0xffffffc80200b9d0: 0xffffffc80200b9f0 0xffffffff8047c526
0xffffffc80200b9e0: 0xffffffc80200ba30 0xffffffff8047fe9a
The assembler dump of the function preambula:
add sp,sp,-16
sd s0,8(sp)
add s0,sp,16
In the fist stack frame, where ra is not stored on the stack we can
observe:
0(sp) 8(sp)
.---------------------------------------------.
sp->| frame->fp | frame->ra (saved fp) |
|---------------------------------------------|
fp->| .... | .... |
|---------------------------------------------|
| | |
and in the code check is performed:
if (regs && (regs->epc == pc) && (frame->fp & 0x7))
I see no reason to check frame->fp value at all, because it is can be
uninitialized value on the stack. A better way is to check frame->ra to
be an address on the stack. After the stacktrace shows as expect:
[<ffffffff804853c2>] regmap_mmio_read32le+0xe/0x1c
[<ffffffff80485758>] regmap_mmio_read+0x24/0x52
[<ffffffff8047c526>] _regmap_bus_reg_read+0x1a/0x22
[<ffffffff8047fe9a>] _regmap_read+0x5c/0xea
[<ffffffff80480376>] _regmap_update_bits+0x76/0xc0
...
---[ end trace 0000000000000000 ]---
As pointed by Samuel Holland it is incorrect to remove check of the stackframe
entirely.
Changes since v2 [2]:
- Add accidentally forgotten curly brace
Changes since v1 [1]:
- Instead of just dropping frame->fp check, replace it with validation of
frame->ra, which should be a stack address.
- Move frame pointer validation into the separate function.
[1] https://lore.kernel.org/linux-riscv/20240426072701.6463-1-dev.mbstr@gmail.com/
[2] https://lore.kernel.org/linux-riscv/20240521131314.48895-1-dev.mbstr@gmail.com/
Fixes: f766f77a74 ("riscv/stacktrace: Fix stack output without ra on the stack top")
Signed-off-by: Matthew Bystrin <dev.mbstr@gmail.com>
Reviewed-by: Samuel Holland <samuel.holland@sifive.com>
Link: https://lore.kernel.org/r/20240521191727.62012-1-dev.mbstr@gmail.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
This commit replaces riscv's support for FTRACE_WITH_REGS with support
for FTRACE_WITH_ARGS. This is required for the ongoing effort to stop
relying on stop_machine() for RISCV's implementation of ftrace.
The main relevant benefit that this change will bring for the above
use-case is that now we don't have separate ftrace_caller and
ftrace_regs_caller trampolines. This will allow the callsite to call
ftrace_caller by modifying a single instruction. Now the callsite can
do something similar to:
When not tracing: | When tracing:
func: func:
auipc t0, ftrace_caller_top auipc t0, ftrace_caller_top
nop <=========<Enable/Disable>=========> jalr t0, ftrace_caller_bottom
[...] [...]
The above assumes that we are dropping the support of calling a direct
trampoline from the callsite. We need to drop this as the callsite can't
change the target address to call, it can only enable/disable a call to
a preset target (ftrace_caller in the above diagram). We can later optimize
this by calling an intermediate dispatcher trampoline before ftrace_caller.
Currently, ftrace_regs_caller saves all CPU registers in the format of
struct pt_regs and allows the tracer to modify them. We don't need to
save all of the CPU registers because at function entry only a subset of
pt_regs is live:
|----------+----------+---------------------------------------------|
| Register | ABI Name | Description |
|----------+----------+---------------------------------------------|
| x1 | ra | Return address for traced function |
| x2 | sp | Stack pointer |
| x5 | t0 | Return address for ftrace_caller trampoline |
| x8 | s0/fp | Frame pointer |
| x10-11 | a0-1 | Function arguments/return values |
| x12-17 | a2-7 | Function arguments |
|----------+----------+---------------------------------------------|
See RISCV calling convention[1] for the above table.
Saving just the live registers decreases the amount of stack space
required from 288 Bytes to 112 Bytes.
Basic testing was done with this on the VisionFive 2 development board.
Note:
- Moving from REGS to ARGS will mean that RISCV will stop supporting
KPROBES_ON_FTRACE as it requires full pt_regs to be saved.
- KPROBES_ON_FTRACE will be supplanted by FPROBES see [2].
[1] https://riscv.org/wp-content/uploads/2015/01/riscv-calling.pdf
[2] https://lore.kernel.org/all/170887410337.564249.6360118840946697039.stgit@devnote2/
Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Reviewed-by: Björn Töpel <bjorn@rivosinc.com>
Link: https://lore.kernel.org/r/20240405142453.4187-1-puranjay@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Samuel Holland <samuel.holland@sifive.com> says:
This series optimizes access_ok() by defining TASK_SIZE_MAX. At Alex's
suggestion, I also tried making TASK_SIZE constant (specifically by
making PGDIR_SHIFT a variable instead of a ternary expression, then
replacing the load with an immediate using ALTERNATIVE). This appeared
to slightly improve performance on some implementations (C906) but
regressed it on others (FU740). So I am leaving further optimizations to
a later series.
* b4-shazam-merge:
riscv: Define TASK_SIZE_MAX for __access_ok()
riscv: Remove PGDIR_SIZE_L3 and TASK_SIZE_MIN
Link: https://lore.kernel.org/r/20240327143858.711792-1-samuel.holland@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Since commit aad15bc85c ("riscv: Change code model of module to
medany to improve data accessing"), kernel modules have not been built
with -fPIC, so they wouldn't have R_RISCV_GOT_HI20 or R_RISCV_CALL_PLT
relocations, and handling of those relocations is unnecessary.
If RELOCATABLE=y, kernel modules will be built with -fPIE, which would
reintroduce said relocations, so only select MODULE_SECTIONS when
RELOCATABLE.
Signed-off-by: Qingfang Deng <qingfang.deng@siflower.com.cn>
Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>
Link: https://lore.kernel.org/r/20240511015725.1162-1-dqfext@gmail.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Previously the build process would always set KBUILD_IMAGE to the
uncompressed Image file (unless XIP_KERNEL or EFI_ZBOOT was enabled) and
unconditionally compress it into Image.gz. However there are already
build targets for Image.bz2, Image.lz4, Image.lzma, Image.lzo and
Image.zstd, so let's make use of those, make the compression method
configurable and set KBUILD_IMAGE accordingly so that targets like
'make install' and 'make bindeb-pkg' will use the chosen image.
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Signed-off-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Reviewed-by: Nicolas Schier <n.schier@avm.de>
Reviewed-by: Masahiro Yamada <masahiroy@kernel.org>
Link: https://lore.kernel.org/r/20240504193446.196886-2-emil.renner.berthing@canonical.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Pull RISC-V updates from Palmer Dabbelt:
- Add byte/half-word compare-and-exchange, emulated via LR/SC loops
- Support for Rust
- Support for Zihintpause in hwprobe
- Add PR_RISCV_SET_ICACHE_FLUSH_CTX prctl()
- Support lockless lockrefs
* tag 'riscv-for-linus-6.10-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (42 commits)
riscv: defconfig: Enable CONFIG_CLK_SOPHGO_CV1800
riscv: select ARCH_HAS_FAST_MULTIPLIER
riscv: mm: still create swiotlb buffer for kmalloc() bouncing if required
riscv: Annotate pgtable_l{4,5}_enabled with __ro_after_init
riscv: Remove redundant CONFIG_64BIT from pgtable_l{4,5}_enabled
riscv: mm: Always use an ASID to flush mm contexts
riscv: mm: Preserve global TLB entries when switching contexts
riscv: mm: Make asid_bits a local variable
riscv: mm: Use a fixed layout for the MM context ID
riscv: mm: Introduce cntx2asid/cntx2version helper macros
riscv: Avoid TLB flush loops when affected by SiFive CIP-1200
riscv: Apply SiFive CIP-1200 workaround to single-ASID sfence.vma
riscv: mm: Combine the SMP and UP TLB flush code
riscv: Only send remote fences when some other CPU is online
riscv: mm: Broadcast kernel TLB flushes only when needed
riscv: Use IPIs for remote cache/TLB flushes by default
riscv: Factor out page table TLB synchronization
riscv: Flush the instruction cache during SMP bringup
riscv: hwprobe: export Zihintpause ISA extension
riscv: misaligned: remove CONFIG_RISCV_M_MODE specific code
...
__kernel_map_pages() is a debug function which clears the valid bit in page
table entry for deallocated pages to detect illegal memory accesses to
freed pages.
This function set/clear the valid bit using __set_memory(). __set_memory()
acquires init_mm's semaphore, and this operation may sleep. This is
problematic, because __kernel_map_pages() can be called in atomic context,
and thus is illegal to sleep. An example warning that this causes:
BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:1578
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 2, name: kthreadd
preempt_count: 2, expected: 0
CPU: 0 PID: 2 Comm: kthreadd Not tainted 6.9.0-g1d4c6d784ef6 #37
Hardware name: riscv-virtio,qemu (DT)
Call Trace:
[<ffffffff800060dc>] dump_backtrace+0x1c/0x24
[<ffffffff8091ef6e>] show_stack+0x2c/0x38
[<ffffffff8092baf8>] dump_stack_lvl+0x5a/0x72
[<ffffffff8092bb24>] dump_stack+0x14/0x1c
[<ffffffff8003b7ac>] __might_resched+0x104/0x10e
[<ffffffff8003b7f4>] __might_sleep+0x3e/0x62
[<ffffffff8093276a>] down_write+0x20/0x72
[<ffffffff8000cf00>] __set_memory+0x82/0x2fa
[<ffffffff8000d324>] __kernel_map_pages+0x5a/0xd4
[<ffffffff80196cca>] __alloc_pages_bulk+0x3b2/0x43a
[<ffffffff8018ee82>] __vmalloc_node_range+0x196/0x6ba
[<ffffffff80011904>] copy_process+0x72c/0x17ec
[<ffffffff80012ab4>] kernel_clone+0x60/0x2fe
[<ffffffff80012f62>] kernel_thread+0x82/0xa0
[<ffffffff8003552c>] kthreadd+0x14a/0x1be
[<ffffffff809357de>] ret_from_fork+0xe/0x1c
Rewrite this function with apply_to_existing_page_range(). It is fine to
not have any locking, because __kernel_map_pages() works with pages being
allocated/deallocated and those pages are not changed by anyone else in the
meantime.
Fixes: 5fde3db5eb ("riscv: add ARCH_SUPPORTS_DEBUG_PAGEALLOC support")
Signed-off-by: Nam Cao <namcao@linutronix.de>
Cc: stable@vger.kernel.org
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/1289ecba9606a19917bc12b6c27da8aa23e1e5ae.1715750938.git.namcao@linutronix.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
debug_pagealloc is a debug feature which clears the valid bit in page table
entry for freed pages to detect illegal accesses to freed memory.
For this feature to work, virtual mapping must have PAGE_SIZE resolution.
(No, we cannot map with huge pages and split them only when needed; because
pages can be allocated/freed in atomic context and page splitting cannot be
done in atomic context)
Force linear mapping to use small pages if debug_pagealloc is enabled.
Note that it is not necessary to force the entire linear mapping, but only
those that are given to memory allocator. Some parts of memory can keep
using huge page mapping (for example, kernel's executable code). But these
parts are minority, so keep it simple. This is just a debug feature, some
extra overhead should be acceptable.
Fixes: 5fde3db5eb ("riscv: add ARCH_SUPPORTS_DEBUG_PAGEALLOC support")
Signed-off-by: Nam Cao <namcao@linutronix.de>
Cc: stable@vger.kernel.org
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/2e391fa6c6f9b3fcf1b41cefbace02ee4ab4bf59.1715750938.git.namcao@linutronix.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Pull more SoC devicetree updates from Arnd Bergmann:
"This is a follow-up to an earlier pull request for device tree
changes, as three platform maintainers sent their contents too late to
be included in the main set, but had not caused any further problems
since then:
- The Amlogic platform now containts support for two new SoC types,
the A4 and A5 chips for audio applications. Both come with a
reference board, and one more dts file gets addded for the
combination of the MNT Reform Laptop with the BPI-CM4 CPU module
- The ASpeed platform adds support for six addititional server
platforms that use ast2500 or ast2600 as their BMC, while another
one gets removed
- The RISC-V platforms from Microchip, Starfive and and T-HEAD get
additional features for existing hardware, plus the addition of the
Milk-V Mars based on the StarFive VisionFive v2 board"
* tag 'soc-dt-late-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (76 commits)
riscv: dts: microchip: add pac1934 power-monitor to icicle
riscv: dts: thead: Fix node ordering in TH1520 device tree
ARM: dts: aspeed: Add ASRock E3C256D4I BMC
dt-bindings: arm: aspeed: document ASRock E3C256D4I
dt-bindings: trivial-devices: add isil,isl69269
ARM: dts: aspeed: x4tf: Add dts for asus x4tf project
dt-bindings: arm: aspeed: add ASUS X4TF board
ARM: dts: aspeed: Remove Facebook Cloudripper dts
ARM: dts: aspeed: drop unused ref_voltage ADC property
ARM: dts: aspeed: harma: correct Mellanox multi-host property
ARM: dts: aspeed: yosemitev2: correct Mellanox multi-host property
ARM: dts: aspeed: yosemite4: correct Mellanox multi-host property
ARM: dts: aspeed: greatlakes: correct Mellanox multi-host property
ARM: dts: aspeed: Modify I2C bus configuration
ARM: dts: aspeed: Disable unused ADC channels for Asrock X570D4U BMC
ARM: dts: aspeed: Modify GPIO table for Asrock X570D4U BMC
ARM: dts: aspeed: yosemite4: set bus13 frequency to 100k
ARM: dts: Aspeed: Bonnell: Fix NVMe LED labels
ARM: dts: aspeed: yosemite4: Enable ipmb device for OCP debug card
ARM: dts: aspeed: ahe50dc: Update lm25066 regulator name
...
Pull mm updates from Andrew Morton:
"The usual shower of singleton fixes and minor series all over MM,
documented (hopefully adequately) in the respective changelogs.
Notable series include:
- Lucas Stach has provided some page-mapping cleanup/consolidation/
maintainability work in the series "mm/treewide: Remove pXd_huge()
API".
- In the series "Allow migrate on protnone reference with
MPOL_PREFERRED_MANY policy", Donet Tom has optimized mempolicy's
MPOL_PREFERRED_MANY mode, yielding almost doubled performance in
one test.
- In their series "Memory allocation profiling" Kent Overstreet and
Suren Baghdasaryan have contributed a means of determining (via
/proc/allocinfo) whereabouts in the kernel memory is being
allocated: number of calls and amount of memory.
- Matthew Wilcox has provided the series "Various significant MM
patches" which does a number of rather unrelated things, but in
largely similar code sites.
- In his series "mm: page_alloc: freelist migratetype hygiene"
Johannes Weiner has fixed the page allocator's handling of
migratetype requests, with resulting improvements in compaction
efficiency.
- In the series "make the hugetlb migration strategy consistent"
Baolin Wang has fixed a hugetlb migration issue, which should
improve hugetlb allocation reliability.
- Liu Shixin has hit an I/O meltdown caused by readahead in a
memory-tight memcg. Addressed in the series "Fix I/O high when
memory almost met memcg limit".
- In the series "mm/filemap: optimize folio adding and splitting"
Kairui Song has optimized pagecache insertion, yielding ~10%
performance improvement in one test.
- Baoquan He has cleaned up and consolidated the early zone
initialization code in the series "mm/mm_init.c: refactor
free_area_init_core()".
- Baoquan has also redone some MM initializatio code in the series
"mm/init: minor clean up and improvement".
- MM helper cleanups from Christoph Hellwig in his series "remove
follow_pfn".
- More cleanups from Matthew Wilcox in the series "Various
page->flags cleanups".
- Vlastimil Babka has contributed maintainability improvements in the
series "memcg_kmem hooks refactoring".
- More folio conversions and cleanups in Matthew Wilcox's series:
"Convert huge_zero_page to huge_zero_folio"
"khugepaged folio conversions"
"Remove page_idle and page_young wrappers"
"Use folio APIs in procfs"
"Clean up __folio_put()"
"Some cleanups for memory-failure"
"Remove page_mapping()"
"More folio compat code removal"
- David Hildenbrand chipped in with "fs/proc/task_mmu: convert
hugetlb functions to work on folis".
- Code consolidation and cleanup work related to GUP's handling of
hugetlbs in Peter Xu's series "mm/gup: Unify hugetlb, part 2".
- Rick Edgecombe has developed some fixes to stack guard gaps in the
series "Cover a guard gap corner case".
- Jinjiang Tu has fixed KSM's behaviour after a fork+exec in the
series "mm/ksm: fix ksm exec support for prctl".
- Baolin Wang has implemented NUMA balancing for multi-size THPs.
This is a simple first-cut implementation for now. The series is
"support multi-size THP numa balancing".
- Cleanups to vma handling helper functions from Matthew Wilcox in
the series "Unify vma_address and vma_pgoff_address".
- Some selftests maintenance work from Dev Jain in the series
"selftests/mm: mremap_test: Optimizations and style fixes".
- Improvements to the swapping of multi-size THPs from Ryan Roberts
in the series "Swap-out mTHP without splitting".
- Kefeng Wang has significantly optimized the handling of arm64's
permission page faults in the series
"arch/mm/fault: accelerate pagefault when badaccess"
"mm: remove arch's private VM_FAULT_BADMAP/BADACCESS"
- GUP cleanups from David Hildenbrand in "mm/gup: consistently call
it GUP-fast".
- hugetlb fault code cleanups from Vishal Moola in "Hugetlb fault
path to use struct vm_fault".
- selftests build fixes from John Hubbard in the series "Fix
selftests/mm build without requiring "make headers"".
- Memory tiering fixes/improvements from Ho-Ren (Jack) Chuang in the
series "Improved Memory Tier Creation for CPUless NUMA Nodes".
Fixes the initialization code so that migration between different
memory types works as intended.
- David Hildenbrand has improved follow_pte() and fixed an errant
driver in the series "mm: follow_pte() improvements and acrn
follow_pte() fixes".
- David also did some cleanup work on large folio mapcounts in his
series "mm: mapcount for large folios + page_mapcount() cleanups".
- Folio conversions in KSM in Alex Shi's series "transfer page to
folio in KSM".
- Barry Song has added some sysfs stats for monitoring multi-size
THP's in the series "mm: add per-order mTHP alloc and swpout
counters".
- Some zswap cleanups from Yosry Ahmed in the series "zswap
same-filled and limit checking cleanups".
- Matthew Wilcox has been looking at buffer_head code and found the
documentation to be lacking. The series is "Improve buffer head
documentation".
- Multi-size THPs get more work, this time from Lance Yang. His
series "mm/madvise: enhance lazyfreeing with mTHP in madvise_free"
optimizes the freeing of these things.
- Kemeng Shi has added more userspace-visible writeback
instrumentation in the series "Improve visibility of writeback".
- Kemeng Shi then sent some maintenance work on top in the series
"Fix and cleanups to page-writeback".
- Matthew Wilcox reduces mmap_lock traffic in the anon vma code in
the series "Improve anon_vma scalability for anon VMAs". Intel's
test bot reported an improbable 3x improvement in one test.
- SeongJae Park adds some DAMON feature work in the series
"mm/damon: add a DAMOS filter type for page granularity access recheck"
"selftests/damon: add DAMOS quota goal test"
- Also some maintenance work in the series
"mm/damon/paddr: simplify page level access re-check for pageout"
"mm/damon: misc fixes and improvements"
- David Hildenbrand has disabled some known-to-fail selftests ni the
series "selftests: mm: cow: flag vmsplice() hugetlb tests as
XFAIL".
- memcg metadata storage optimizations from Shakeel Butt in "memcg:
reduce memory consumption by memcg stats".
- DAX fixes and maintenance work from Vishal Verma in the series
"dax/bus.c: Fixups for dax-bus locking""
* tag 'mm-stable-2024-05-17-19-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (426 commits)
memcg, oom: cleanup unused memcg_oom_gfp_mask and memcg_oom_order
selftests/mm: hugetlb_madv_vs_map: avoid test skipping by querying hugepage size at runtime
mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_wp
mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_fault
selftests: cgroup: add tests to verify the zswap writeback path
mm: memcg: make alloc_mem_cgroup_per_node_info() return bool
mm/damon/core: fix return value from damos_wmark_metric_value
mm: do not update memcg stats for NR_{FILE/SHMEM}_PMDMAPPED
selftests: cgroup: remove redundant enabling of memory controller
Docs/mm/damon/maintainer-profile: allow posting patches based on damon/next tree
Docs/mm/damon/maintainer-profile: change the maintainer's timezone from PST to PT
Docs/mm/damon/design: use a list for supported filters
Docs/admin-guide/mm/damon/usage: fix wrong schemes effective quota update command
Docs/admin-guide/mm/damon/usage: fix wrong example of DAMOS filter matching sysfs file
selftests/damon: classify tests for functionalities and regressions
selftests/damon/_damon_sysfs: use 'is' instead of '==' for 'None'
selftests/damon/_damon_sysfs: find sysfs mount point from /proc/mounts
selftests/damon/_damon_sysfs: check errors from nr_schemes file reads
mm/damon/core: initialize ->esz_bp from damos_quota_init_priv()
selftests/damon: add a test for DAMOS quota goal
...
