In addition to We have a handful of new features for 5.14:
* Support for transparent huge pages.
* Support for generic PCI resources mapping.
* Support for the mem= kernel parameter.
* Support for KFENCE.
* A handful of fixes to avoid W+X mappings in the kernel.
* Support for VMAP_STACK based overflow detection.
* An optimized copy_{to,from}_user.
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Merge tag 'riscv-for-linus-5.14-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V updates from Palmer Dabbelt:
"We have a handful of new features for 5.14:
- Support for transparent huge pages.
- Support for generic PCI resources mapping.
- Support for the mem= kernel parameter.
- Support for KFENCE.
- A handful of fixes to avoid W+X mappings in the kernel.
- Support for VMAP_STACK based overflow detection.
- An optimized copy_{to,from}_user"
* tag 'riscv-for-linus-5.14-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (37 commits)
riscv: xip: Fix duplicate included asm/pgtable.h
riscv: Fix PTDUMP output now BPF region moved back to module region
riscv: __asm_copy_to-from_user: Optimize unaligned memory access and pipeline stall
riscv: add VMAP_STACK overflow detection
riscv: ptrace: add argn syntax
riscv: mm: fix build errors caused by mk_pmd()
riscv: Introduce structure that group all variables regarding kernel mapping
riscv: Map the kernel with correct permissions the first time
riscv: Introduce set_kernel_memory helper
riscv: Enable KFENCE for riscv64
RISC-V: Use asm-generic for {in,out}{bwlq}
riscv: add ASID-based tlbflushing methods
riscv: pass the mm_struct to __sbi_tlb_flush_range
riscv: Add mem kernel parameter support
riscv: Simplify xip and !xip kernel address conversion macros
riscv: Remove CONFIG_PHYS_RAM_BASE_FIXED
riscv: Only initialize swiotlb when necessary
riscv: fix typo in init.c
riscv: Cleanup unused functions
riscv: mm: Use better bitmap_zalloc()
...
Clean up the following includecheck warning:
./arch/riscv/kernel/vmlinux-xip.lds.S: asm/pgtable.h is included more
than once.
No functional change.
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
We have a lot of variables that are used to hold kernel mapping addresses,
offsets between physical and virtual mappings and some others used for XIP
kernels: they are all defined at different places in mm/init.c, so group
them into a single structure with, for some of them, more explicit and concise
names.
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
This contains both the short-term fix for the W+X boot mappings and the
larger cleanup.
* riscv-wx-mappings:
riscv: Map the kernel with correct permissions the first time
riscv: Introduce set_kernel_memory helper
riscv: Simplify xip and !xip kernel address conversion macros
riscv: Remove CONFIG_PHYS_RAM_BASE_FIXED
riscv: mm: Fix W+X mappings at boot
For 64-bit kernels, we map all the kernel with write and execute
permissions and afterwards remove writability from text and executability
from data.
For 32-bit kernels, the kernel mapping resides in the linear mapping, so we
map all the linear mapping as writable and executable and afterwards we
remove those properties for unused memory and kernel mapping as
described above.
Change this behavior to directly map the kernel with correct permissions
and avoid going through the whole mapping to fix the permissions.
At the same time, this fixes an issue introduced by commit 2bfc6cd81b
("riscv: Move kernel mapping outside of linear mapping") as reported
here https://github.com/starfive-tech/linux/issues/17.
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
- Changes to core scheduling facilities:
- Add "Core Scheduling" via CONFIG_SCHED_CORE=y, which enables
coordinated scheduling across SMT siblings. This is a much
requested feature for cloud computing platforms, to allow
the flexible utilization of SMT siblings, without exposing
untrusted domains to information leaks & side channels, plus
to ensure more deterministic computing performance on SMT
systems used by heterogenous workloads.
There's new prctls to set core scheduling groups, which
allows more flexible management of workloads that can share
siblings.
- Fix task->state access anti-patterns that may result in missed
wakeups and rename it to ->__state in the process to catch new
abuses.
- Load-balancing changes:
- Tweak newidle_balance for fair-sched, to improve
'memcache'-like workloads.
- "Age" (decay) average idle time, to better track & improve workloads
such as 'tbench'.
- Fix & improve energy-aware (EAS) balancing logic & metrics.
- Fix & improve the uclamp metrics.
- Fix task migration (taskset) corner case on !CONFIG_CPUSET.
- Fix RT and deadline utilization tracking across policy changes
- Introduce a "burstable" CFS controller via cgroups, which allows
bursty CPU-bound workloads to borrow a bit against their future
quota to improve overall latencies & batching. Can be tweaked
via /sys/fs/cgroup/cpu/<X>/cpu.cfs_burst_us.
- Rework assymetric topology/capacity detection & handling.
- Scheduler statistics & tooling:
- Disable delayacct by default, but add a sysctl to enable
it at runtime if tooling needs it. Use static keys and
other optimizations to make it more palatable.
- Use sched_clock() in delayacct, instead of ktime_get_ns().
- Misc cleanups and fixes.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'sched-core-2021-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler udpates from Ingo Molnar:
- Changes to core scheduling facilities:
- Add "Core Scheduling" via CONFIG_SCHED_CORE=y, which enables
coordinated scheduling across SMT siblings. This is a much
requested feature for cloud computing platforms, to allow the
flexible utilization of SMT siblings, without exposing untrusted
domains to information leaks & side channels, plus to ensure more
deterministic computing performance on SMT systems used by
heterogenous workloads.
There are new prctls to set core scheduling groups, which allows
more flexible management of workloads that can share siblings.
- Fix task->state access anti-patterns that may result in missed
wakeups and rename it to ->__state in the process to catch new
abuses.
- Load-balancing changes:
- Tweak newidle_balance for fair-sched, to improve 'memcache'-like
workloads.
- "Age" (decay) average idle time, to better track & improve
workloads such as 'tbench'.
- Fix & improve energy-aware (EAS) balancing logic & metrics.
- Fix & improve the uclamp metrics.
- Fix task migration (taskset) corner case on !CONFIG_CPUSET.
- Fix RT and deadline utilization tracking across policy changes
- Introduce a "burstable" CFS controller via cgroups, which allows
bursty CPU-bound workloads to borrow a bit against their future
quota to improve overall latencies & batching. Can be tweaked via
/sys/fs/cgroup/cpu/<X>/cpu.cfs_burst_us.
- Rework assymetric topology/capacity detection & handling.
- Scheduler statistics & tooling:
- Disable delayacct by default, but add a sysctl to enable it at
runtime if tooling needs it. Use static keys and other
optimizations to make it more palatable.
- Use sched_clock() in delayacct, instead of ktime_get_ns().
- Misc cleanups and fixes.
* tag 'sched-core-2021-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (72 commits)
sched/doc: Update the CPU capacity asymmetry bits
sched/topology: Rework CPU capacity asymmetry detection
sched/core: Introduce SD_ASYM_CPUCAPACITY_FULL sched_domain flag
psi: Fix race between psi_trigger_create/destroy
sched/fair: Introduce the burstable CFS controller
sched/uclamp: Fix uclamp_tg_restrict()
sched/rt: Fix Deadline utilization tracking during policy change
sched/rt: Fix RT utilization tracking during policy change
sched: Change task_struct::state
sched,arch: Remove unused TASK_STATE offsets
sched,timer: Use __set_current_state()
sched: Add get_current_state()
sched,perf,kvm: Fix preemption condition
sched: Introduce task_is_running()
sched: Unbreak wakeups
sched/fair: Age the average idle time
sched/cpufreq: Consider reduced CPU capacity in energy calculation
sched/fair: Take thermal pressure into account while estimating energy
thermal/cpufreq_cooling: Update offline CPUs per-cpu thermal_pressure
sched/fair: Return early from update_tg_cfs_load() if delta == 0
...
- Platform PMU driver updates:
- x86 Intel uncore driver updates for Skylake (SNR) and Icelake (ICX) servers
- Fix RDPMC support
- Fix [extended-]PEBS-via-PT support
- Fix Sapphire Rapids event constraints
- Fix :ppp support on Sapphire Rapids
- Fix fixed counter sanity check on Alder Lake & X86_FEATURE_HYBRID_CPU
- Other heterogenous-PMU fixes
- Kprobes:
- Remove the unused and misguided kprobe::fault_handler callbacks.
- Warn about kprobes taking a page fault.
- Fix the 'nmissed' stat counter.
- Misc cleanups and fixes.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'perf-core-2021-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf events updates from Ingo Molnar:
- Platform PMU driver updates:
- x86 Intel uncore driver updates for Skylake (SNR) and Icelake (ICX) servers
- Fix RDPMC support
- Fix [extended-]PEBS-via-PT support
- Fix Sapphire Rapids event constraints
- Fix :ppp support on Sapphire Rapids
- Fix fixed counter sanity check on Alder Lake & X86_FEATURE_HYBRID_CPU
- Other heterogenous-PMU fixes
- Kprobes:
- Remove the unused and misguided kprobe::fault_handler callbacks.
- Warn about kprobes taking a page fault.
- Fix the 'nmissed' stat counter.
- Misc cleanups and fixes.
* tag 'perf-core-2021-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf: Fix task context PMU for Hetero
perf/x86/intel: Fix instructions:ppp support in Sapphire Rapids
perf/x86/intel: Add more events requires FRONTEND MSR on Sapphire Rapids
perf/x86/intel: Fix fixed counter check warning for some Alder Lake
perf/x86/intel: Fix PEBS-via-PT reload base value for Extended PEBS
perf/x86: Reset the dirty counter to prevent the leak for an RDPMC task
kprobes: Do not increment probe miss count in the fault handler
x86,kprobes: WARN if kprobes tries to handle a fault
kprobes: Remove kprobe::fault_handler
uprobes: Update uprobe_write_opcode() kernel-doc comment
perf/hw_breakpoint: Fix DocBook warnings in perf hw_breakpoint
perf/core: Fix DocBook warnings
perf/core: Make local function perf_pmu_snapshot_aux() static
perf/x86/intel/uncore: Enable I/O stacks to IIO PMON mapping on ICX
perf/x86/intel/uncore: Enable I/O stacks to IIO PMON mapping on SNR
perf/x86/intel/uncore: Generalize I/O stacks to PMON mapping procedure
perf/x86/intel/uncore: Drop unnecessary NULL checks after container_of()
Replace a bunch of 'p->state == TASK_RUNNING' with a new helper:
task_is_running(p).
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Davidlohr Bueso <dave@stgolabs.net>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210611082838.222401495@infradead.org
This commit in sched/urgent moved the cfs_rq_is_decayed() function:
a7b359fc6a37: ("sched/fair: Correctly insert cfs_rq's to list on unthrottle")
and this fresh commit in sched/core modified it in the old location:
9e077b52d86a: ("sched/pelt: Check that *_avg are null when *_sum are")
Merge the two variants.
Conflicts:
kernel/sched/fair.c
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The SWIOTLB buffer is not needed unless the physical address space
is beyond the limit of dma, only initialize swiotlb when swiotlb_force
is true or not all system memory is DMA-able.
Also move the swiotlb_init() into mem_init().
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
RISCV_ERRATA_ALTERNATIVE patches text at runtime which is currently
not possible when the kernel is executed from the flash in XIP mode.
Since runtime patching concerns only traps at the moment, let's just
have all the traps reside in RAM anyway if RISCV_ERRATA_ALTERNATIVE
is set. Thus, these functions will be patch-able even when the .text
section is in flash.
Signed-off-by: Vitaly Wool <vitaly.wool@konsulko.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Kprobes has a counter 'nmissed', that is used to count the number of
times a probe handler was not called. This generally happens when we hit
a kprobe while handling another kprobe.
However, if one of the probe handlers causes a fault, we are currently
incrementing 'nmissed'. The comment in fault handler indicates that this
can be used to account faults taken by the probe handlers. But, this has
never been the intention as is evident from the comment above 'nmissed'
in 'struct kprobe':
/*count the number of times this probe was temporarily disarmed */
unsigned long nmissed;
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lkml.kernel.org/r/20210601120150.672652-1-naveen.n.rao@linux.vnet.ibm.com
`memblock_free()` takes a physical address as its first argument.
Fix the wrong usages in `init_resources()`.
Fixes: ffe0e52612 ("RISC-V: Improve init_resources()")
Fixes: 797f0375dd ("RISC-V: Do not allocate memblock while iterating reserved memblocks")
Signed-off-by: Wende Tan <twd2.me@gmail.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
The reason for kprobe::fault_handler(), as given by their comment:
* We come here because instructions in the pre/post
* handler caused the page_fault, this could happen
* if handler tries to access user space by
* copy_from_user(), get_user() etc. Let the
* user-specified handler try to fix it first.
Is just plain bad. Those other handlers are ran from non-preemptible
context and had better use _nofault() functions. Also, there is no
upstream usage of this.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20210525073213.561116662@infradead.org
These functions are not needed after booting, so mark them as __init
to move them to the __init section.
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Inspired by commit ba090f9caf ("arm64: kprobes: Remove redundant
kprobe_step_ctx"), the ss_pending and match_addr of kprobe_step_ctx
are redundant because those can be replaced by KPROBE_HIT_SS and
&cur_kprobe->ainsn.api.insn[0] + GET_INSN_LENGTH(cur->opcode)
respectively.
Remove the kprobe_step_ctx to simplify the code.
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
The has_fpu check sits at hot code path: switch_to(). Currently, has_fpu
is a bool variable if FPU=y, switch_to() checks it each time, we can
optimize out this check by turning the has_fpu into a static key.
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Fixes the following W=1 build warning(s):
In file included from include/linux/kexec.h:28,
from arch/riscv/kernel/machine_kexec.c:7:
arch/riscv/include/asm/kexec.h:45:1: warning: ‘extern’ is not at beginning of declaration [-Wold-style-declaration]
45 | const extern unsigned char riscv_kexec_relocate[];
| ^~~~~
arch/riscv/include/asm/kexec.h:46:1: warning: ‘extern’ is not at beginning of declaration [-Wold-style-declaration]
46 | const extern unsigned int riscv_kexec_relocate_size;
| ^~~~~
arch/riscv/kernel/machine_kexec.c:125:6: warning: no previous prototype for ‘machine_shutdown’ [-Wmissing-prototypes]
125 | void machine_shutdown(void)
| ^~~~~~~~~~~~~~~~
arch/riscv/kernel/machine_kexec.c:147:1: warning: no previous prototype for ‘machine_crash_shutdown’ [-Wmissing-prototypes]
147 | machine_crash_shutdown(struct pt_regs *regs)
| ^~~~~~~~~~~~~~~~~~~~~~
arch/riscv/kernel/machine_kexec.c:23: warning: Function parameter or member 'image' not described in 'kexec_image_info'
arch/riscv/kernel/machine_kexec.c:53: warning: Function parameter or member 'image' not described in 'machine_kexec_prepare'
arch/riscv/kernel/machine_kexec.c:114: warning: Function parameter or member 'image' not described in 'machine_kexec_cleanup'
arch/riscv/kernel/machine_kexec.c:148: warning: Function parameter or member 'regs' not described in 'machine_crash_shutdown'
arch/riscv/kernel/machine_kexec.c:167: warning: Function parameter or member 'image' not described in 'machine_kexec'
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
lkp reported a randconfig failure:
arch/riscv/kernel/probes/kprobes.c:90:22: error: use of undeclared identifier 'PAGE_KERNEL_READ_EXEC'
We implemented the alloc_insn_page() to allocate PAGE_KERNEL_READ_EXEC
page for kprobes insn page for STRICT_MODULE_RWX. But if MMU=n, we
should fall back to the generic weak alloc_insn_page() by generic
kprobe subsystem.
Fixes: cdd1b2bd35 ("riscv: kprobes: Implement alloc_insn_page()")
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
As [1] and [2] said, the arch_stack_walk should not to trace itself, or it will
leave the trace unexpectedly when called. The example is when we do "cat
/sys/kernel/debug/page_owner", all pages' stack is the same.
arch_stack_walk+0x18/0x20
stack_trace_save+0x40/0x60
register_dummy_stack+0x24/0x5e
init_page_owner+0x2e
So we use __builtin_frame_address(1) as the first frame to be walked. And mark
the arch_stack_walk() noinline.
We found that pr_cont will affact pages' stack whose task state is RUNNING when
testing "echo t > /proc/sysrq-trigger". So move the place of pr_cont and mark
the function dump_backtrace() noinline.
Also we move the case when task == NULL into else branch, and test for it in
"echo c > /proc/sysrq-trigger".
[1] https://lore.kernel.org/lkml/20210319184106.5688-1-mark.rutland@arm.com/
[2] https://lore.kernel.org/lkml/20210317142050.57712-1-chenjun102@huawei.com/
Signed-off-by: Chen Huang <chenhuang5@huawei.com>
Fixes: 5d8544e2d0 ("RISC-V: Generic library routines and assembly")
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
As pointed out by commit
de9b8f5dcb ("sched: Fix crash trying to dequeue/enqueue the idle thread")
init_idle() can and will be invoked more than once on the same idle
task. At boot time, it is invoked for the boot CPU thread by
sched_init(). Then smp_init() creates the threads for all the secondary
CPUs and invokes init_idle() on them.
As the hotplug machinery brings the secondaries to life, it will issue
calls to idle_thread_get(), which itself invokes init_idle() yet again.
In this case it's invoked twice more per secondary: at _cpu_up(), and at
bringup_cpu().
Given smp_init() already initializes the idle tasks for all *possible*
CPUs, no further initialization should be required. Now, removing
init_idle() from idle_thread_get() exposes some interesting expectations
with regards to the idle task's preempt_count: the secondary startup always
issues a preempt_disable(), requiring some reset of the preempt count to 0
between hot-unplug and hotplug, which is currently served by
idle_thread_get() -> idle_init().
Given the idle task is supposed to have preemption disabled once and never
see it re-enabled, it seems that what we actually want is to initialize its
preempt_count to PREEMPT_DISABLED and leave it there. Do that, and remove
init_idle() from idle_thread_get().
Secondary startups were patched via coccinelle:
@begone@
@@
-preempt_disable();
...
cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210512094636.2958515-1-valentin.schneider@arm.com
Since commit 79b1feba54 ("RISC-V: Setup exception vector early")
exception vectors are setup early and the handle_exception symbol from
the asm files is no longer referenced in traps.c. Remove it.
Signed-off-by: Rouven Czerwinski <rouven@czerwinskis.de>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
The various uses of protect_kernel_linear_mapping_text_rodata() are
not consistent:
- Its definition depends on "64BIT && !XIP_KERNEL",
- Its forward declaration depends on MMU,
- Its single caller depends on "STRICT_KERNEL_RWX && 64BIT && MMU &&
!XIP_KERNEL".
Fix this by settling on the dependencies of the caller, which can be
simplified as STRICT_KERNEL_RWX depends on "MMU && !XIP_KERNEL".
Provide a dummy definition, as the caller is protected by
"IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)" instead of "#ifdef
CONFIG_STRICT_KERNEL_RWX".
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Alexandre Ghiti <alex@ghiti.fr>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
* Support for the memtest= kernel command-line argument.
* Support for building the kernel with FORTIFY_SOURCE.
* Support for generic clockevent broadcasts.
* Support for the buildtar build target.
* Some build system cleanups to pass more LLVM-friendly arguments.
* Support for kprobes.
* A rearranged kernel memory map, the first part of supporting sv48
systems.
* Improvements to kexec, along with support for kdump and crash kernels.
* An alternatives-based errata framework, along with support for
handling a pair of errata that manifest on some SiFive designs
(including the HiFive Unmatched).
* Support for XIP.
* A device tree for the Microchip PolarFire ICICLE SoC and associated
dev board.
Along with a bunch of cleanups. There are already a handful of fixes
on the list so there will likely be a part 2.
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Merge tag 'riscv-for-linus-5.13-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V updates from Palmer Dabbelt:
- Support for the memtest= kernel command-line argument.
- Support for building the kernel with FORTIFY_SOURCE.
- Support for generic clockevent broadcasts.
- Support for the buildtar build target.
- Some build system cleanups to pass more LLVM-friendly arguments.
- Support for kprobes.
- A rearranged kernel memory map, the first part of supporting sv48
systems.
- Improvements to kexec, along with support for kdump and crash
kernels.
- An alternatives-based errata framework, along with support for
handling a pair of errata that manifest on some SiFive designs
(including the HiFive Unmatched).
- Support for XIP.
- A device tree for the Microchip PolarFire ICICLE SoC and associated
dev board.
... along with a bunch of cleanups. There are already a handful of fixes
on the list so there will likely be a part 2.
* tag 'riscv-for-linus-5.13-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (45 commits)
RISC-V: Always define XIP_FIXUP
riscv: Remove 32b kernel mapping from page table dump
riscv: Fix 32b kernel build with CONFIG_DEBUG_VIRTUAL=y
RISC-V: Fix error code returned by riscv_hartid_to_cpuid()
RISC-V: Enable Microchip PolarFire ICICLE SoC
RISC-V: Initial DTS for Microchip ICICLE board
dt-bindings: riscv: microchip: Add YAML documentation for the PolarFire SoC
RISC-V: Add Microchip PolarFire SoC kconfig option
RISC-V: enable XIP
RISC-V: Add crash kernel support
RISC-V: Add kdump support
RISC-V: Improve init_resources()
RISC-V: Add kexec support
RISC-V: Add EM_RISCV to kexec UAPI header
riscv: vdso: fix and clean-up Makefile
riscv/mm: Use BUG_ON instead of if condition followed by BUG.
riscv/kprobe: fix kernel panic when invoking sys_read traced by kprobe
riscv: Set ARCH_HAS_STRICT_MODULE_RWX if MMU
riscv: module: Create module allocations without exec permissions
riscv: bpf: Avoid breaking W^X
...
We should return a negative error code upon failure in
riscv_hartid_to_cpuid() instead of NR_CPUS. This is also
aligned with all uses of riscv_hartid_to_cpuid() which
expect negative error code upon failure.
Fixes: 6825c7a80f ("RISC-V: Add logical CPU indexing for RISC-V")
Fixes: f99fb607fb ("RISC-V: Use Linux logical CPU number instead of hartid")
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Introduce XIP (eXecute In Place) support for RISC-V platforms.
It allows code to be executed directly from non-volatile storage
directly addressable by the CPU, such as QSPI NOR flash which can
be found on many RISC-V platforms. This makes way for significant
optimization of RAM footprint. The XIP kernel is not compressed
since it has to run directly from flash, so it will occupy more
space on the non-volatile storage. The physical flash address used
to link the kernel object files and for storing it has to be known
at compile time and is represented by a Kconfig option.
XIP on RISC-V will for the time being only work on MMU-enabled
kernels.
Signed-off-by: Vitaly Wool <vitaly.wool@konsulko.com>
[Alex: Rebase on top of "Move kernel mapping outside the linear mapping" ]
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
[Palmer: disable XIP for allyesconfig]
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
This patch allows Linux to act as a crash kernel for use with
kdump. Userspace will let the crash kernel know about the
memory region it can use through linux,usable-memory property
on the /memory node (overriding its reg property), and about the
memory region where the elf core header of the previous kernel
is saved, through a reserved-memory node with a compatible string
of "linux,elfcorehdr". This approach is the least invasive and
re-uses functionality already present.
I tested this on riscv64 qemu and it works as expected, you
may test it by retrieving the dmesg of the previous kernel
through /proc/vmcore, using the vmcore-dmesg utility from
kexec-tools.
Signed-off-by: Nick Kossifidis <mick@ics.forth.gr>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
This patch adds support for kdump, the kernel will reserve a
region for the crash kernel and jump there on panic. In order
for userspace tools (kexec-tools) to prepare the crash kernel
kexec image, we also need to expose some information on
/proc/iomem for the memory regions used by the kernel and for
the region reserved for crash kernel. Note that on userspace
the device tree is used to determine the system's memory
layout so the "System RAM" on /proc/iomem is ignored.
I tested this on riscv64 qemu and works as expected, you may
test it by triggering a crash through /proc/sysrq_trigger:
echo c > /proc/sysrq_trigger
Signed-off-by: Nick Kossifidis <mick@ics.forth.gr>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
The kernel region is always present and we know where it is, no need to
look for it inside the loop, just ignore it like the rest of the
reserved regions within system's memory.
Additionally, we don't need to call memblock_free inside the loop, as if
called it'll split the region of pre-allocated resources in two parts,
messing things up, just re-use the previous pre-allocated resource and
free any unused resources after both loops finish.
Signed-off-by: Nick Kossifidis <mick@ics.forth.gr>
[Palmer: commit text]
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
This patch adds support for kexec on RISC-V. On SMP systems it depends
on HOTPLUG_CPU in order to be able to bring up all harts after kexec.
It also needs a recent OpenSBI version that supports the HSM extension.
I tested it on riscv64 QEMU on both an smp and a non-smp system.
Signed-off-by: Nick Kossifidis <mick@ics.forth.gr>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Running "make" on an already compiled kernel tree will rebuild the
kernel even without any modifications:
CALL linux/scripts/checksyscalls.sh
CALL linux/scripts/atomic/check-atomics.sh
CHK include/generated/compile.h
SO2S arch/riscv/kernel/vdso/vdso-syms.S
AS arch/riscv/kernel/vdso/vdso-syms.o
AR arch/riscv/kernel/vdso/built-in.a
AR arch/riscv/kernel/built-in.a
AR arch/riscv/built-in.a
GEN .version
CHK include/generated/compile.h
UPD include/generated/compile.h
CC init/version.o
AR init/built-in.a
LD vmlinux.o
The reason is "Any target that utilizes if_changed must be listed in
$(targets), otherwise the command line check will fail, and the target
will always be built" as explained by Documentation/kbuild/makefiles.rst
Fix this build bug by adding vdso-syms.S to $(targets)
At the same time, there are two trivial clean up modifications:
- the vdso-dummy.o is not needed any more after so remove it.
- vdso.lds is a generated file, so it should be prefixed with
$(obj)/ instead of $(src)/
Fixes: c2c81bb2f6 ("RISC-V: Fix the VDSO symbol generaton for binutils-2.35+")
Cc: stable@vger.kernel.org
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
The execution of sys_read end up hitting a BUG_ON() in __find_get_block
after installing kprobe at sys_read, the BUG message like the following:
[ 65.708663] ------------[ cut here ]------------
[ 65.709987] kernel BUG at fs/buffer.c:1251!
[ 65.711283] Kernel BUG [#1]
[ 65.712032] Modules linked in:
[ 65.712925] CPU: 0 PID: 51 Comm: sh Not tainted 5.12.0-rc4 #1
[ 65.714407] Hardware name: riscv-virtio,qemu (DT)
[ 65.715696] epc : __find_get_block+0x218/0x2c8
[ 65.716835] ra : __getblk_gfp+0x1c/0x4a
[ 65.717831] epc : ffffffe00019f11e ra : ffffffe00019f56a sp : ffffffe002437930
[ 65.719553] gp : ffffffe000f06030 tp : ffffffe0015abc00 t0 : ffffffe00191e038
[ 65.721290] t1 : ffffffe00191e038 t2 : 000000000000000a s0 : ffffffe002437960
[ 65.723051] s1 : ffffffe00160ad00 a0 : ffffffe00160ad00 a1 : 000000000000012a
[ 65.724772] a2 : 0000000000000400 a3 : 0000000000000008 a4 : 0000000000000040
[ 65.726545] a5 : 0000000000000000 a6 : ffffffe00191e000 a7 : 0000000000000000
[ 65.728308] s2 : 000000000000012a s3 : 0000000000000400 s4 : 0000000000000008
[ 65.730049] s5 : 000000000000006c s6 : ffffffe00240f800 s7 : ffffffe000f080a8
[ 65.731802] s8 : 0000000000000001 s9 : 000000000000012a s10: 0000000000000008
[ 65.733516] s11: 0000000000000008 t3 : 00000000000003ff t4 : 000000000000000f
[ 65.734434] t5 : 00000000000003ff t6 : 0000000000040000
[ 65.734613] status: 0000000000000100 badaddr: 0000000000000000 cause: 0000000000000003
[ 65.734901] Call Trace:
[ 65.735076] [<ffffffe00019f11e>] __find_get_block+0x218/0x2c8
[ 65.735417] [<ffffffe00020017a>] __ext4_get_inode_loc+0xb2/0x2f6
[ 65.735618] [<ffffffe000201b6c>] ext4_get_inode_loc+0x3a/0x8a
[ 65.735802] [<ffffffe000203380>] ext4_reserve_inode_write+0x2e/0x8c
[ 65.735999] [<ffffffe00020357a>] __ext4_mark_inode_dirty+0x4c/0x18e
[ 65.736208] [<ffffffe000206bb0>] ext4_dirty_inode+0x46/0x66
[ 65.736387] [<ffffffe000192914>] __mark_inode_dirty+0x12c/0x3da
[ 65.736576] [<ffffffe000180dd2>] touch_atime+0x146/0x150
[ 65.736748] [<ffffffe00010d762>] filemap_read+0x234/0x246
[ 65.736920] [<ffffffe00010d834>] generic_file_read_iter+0xc0/0x114
[ 65.737114] [<ffffffe0001f5d7a>] ext4_file_read_iter+0x42/0xea
[ 65.737310] [<ffffffe000163f2c>] new_sync_read+0xe2/0x15a
[ 65.737483] [<ffffffe000165814>] vfs_read+0xca/0xf2
[ 65.737641] [<ffffffe000165bae>] ksys_read+0x5e/0xc8
[ 65.737816] [<ffffffe000165c26>] sys_read+0xe/0x16
[ 65.737973] [<ffffffe000003972>] ret_from_syscall+0x0/0x2
[ 65.738858] ---[ end trace fe93f985456c935d ]---
A simple reproducer looks like:
echo 'p:myprobe sys_read fd=%a0 buf=%a1 count=%a2' > /sys/kernel/debug/tracing/kprobe_events
echo 1 > /sys/kernel/debug/tracing/events/kprobes/myprobe/enable
cat /sys/kernel/debug/tracing/trace
Here's what happens to hit that BUG_ON():
1) After installing kprobe at entry of sys_read, the first instruction
is replaced by 'ebreak' instruction on riscv64 platform.
2) Once kernel reach the 'ebreak' instruction at the entry of sys_read,
it trap into the riscv breakpoint handler, where it do something to
setup for coming single-step of origin instruction, including backup
the 'sstatus' in pt_regs, followed by disable interrupt during single
stepping via clear 'SIE' bit of 'sstatus' in pt_regs.
3) Then kernel restore to the instruction slot contains two instructions,
one is original instruction at entry of sys_read, the other is 'ebreak'.
Here it trigger a 'Instruction page fault' exception (value at 'scause'
is '0xc'), if PF is not filled into PageTabe for that slot yet.
4) Again kernel trap into page fault exception handler, where it choose
different policy according to the state of running kprobe. Because
afte 2) the state is KPROBE_HIT_SS, so kernel reset the current kprobe
and 'pc' points back to the probe address.
5) Because 'epc' point back to 'ebreak' instrution at sys_read probe,
kernel trap into breakpoint handler again, and repeat the operations
at 2), however 'sstatus' without 'SIE' is keep at 4), it cause the
real 'sstatus' saved at 2) is overwritten by the one withou 'SIE'.
6) When kernel cross the probe the 'sstatus' CSR restore with value
without 'SIE', and reach __find_get_block where it requires the
interrupt must be enabled.
Fix this is very trivial, just restore the value of 'sstatus' in pt_regs
with backup one at 2) when the instruction being single stepped cause a
page fault.
Fixes: c22b0bcb1d ("riscv: Add kprobes supported")
Signed-off-by: Liao Chang <liaochang1@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
The core code manages the executable permissions of code regions of
modules explicitly, it is not necessary to create the module vmalloc
regions with RWX permissions. Create them with RW- permissions instead.
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Allocate PAGE_KERNEL_READ_EXEC(read only, executable) page for kprobes
insn page. This is to prepare for STRICT_MODULE_RWX.
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Constify the sbi_ipi_ops so that it will be placed in the .rodata
section. This will cause attempts to modify it to fail when strict
page permissions are in place.
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Constify the sys_call_table so that it will be placed in the .rodata
section. This will cause attempts to modify the table to fail when
strict page permissions are in place.
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
All of these are never modified after init, so they can be
__ro_after_init.
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
They are not needed after booting, so mark them as __init to move them
to the __init section.
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
This is a preparatory patch for relocatable kernel and sv48 support.
The kernel used to be linked at PAGE_OFFSET address therefore we could use
the linear mapping for the kernel mapping. But the relocated kernel base
address will be different from PAGE_OFFSET and since in the linear mapping,
two different virtual addresses cannot point to the same physical address,
the kernel mapping needs to lie outside the linear mapping so that we don't
have to copy it at the same physical offset.
The kernel mapping is moved to the last 2GB of the address space, BPF
is now always after the kernel and modules use the 2GB memory range right
before the kernel, so BPF and modules regions do not overlap. KASLR
implementation will simply have to move the kernel in the last 2GB range
and just take care of leaving enough space for BPF.
In addition, by moving the kernel to the end of the address space, both
sv39 and sv48 kernels will be exactly the same without needing to be
relocated at runtime.
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
[Palmer: Squash the STRICT_RWX fix, and a !MMU fix]
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Prior to clang 13.0.0, the RISC-V name for the mcount symbol was
"mcount", which differs from the GCC version of "_mcount", which results
in the following errors:
riscv64-linux-gnu-ld: init/main.o: in function `__traceiter_initcall_level':
main.c:(.text+0xe): undefined reference to `mcount'
riscv64-linux-gnu-ld: init/main.o: in function `__traceiter_initcall_start':
main.c:(.text+0x4e): undefined reference to `mcount'
riscv64-linux-gnu-ld: init/main.o: in function `__traceiter_initcall_finish':
main.c:(.text+0x92): undefined reference to `mcount'
riscv64-linux-gnu-ld: init/main.o: in function `.LBB32_28':
main.c:(.text+0x30c): undefined reference to `mcount'
riscv64-linux-gnu-ld: init/main.o: in function `free_initmem':
main.c:(.text+0x54c): undefined reference to `mcount'
This has been corrected in https://reviews.llvm.org/D98881 but the
minimum supported clang version is 10.0.1. To avoid build errors and to
gain a working function tracer, adjust the name of the mcount symbol for
older versions of clang in mount.S and recordmcount.pl.
Link: https://github.com/ClangBuiltLinux/linux/issues/1331
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Currently, the VDSO is being linked through $(CC). This does not match
how the rest of the kernel links objects, which is through the $(LD)
variable.
When linking with clang, there are a couple of warnings about flags that
will not be used during the link:
clang-12: warning: argument unused during compilation: '-no-pie' [-Wunused-command-line-argument]
clang-12: warning: argument unused during compilation: '-pg' [-Wunused-command-line-argument]
'-no-pie' was added in commit 85602bea29 ("RISC-V: build vdso-dummy.o
with -no-pie") to override '-pie' getting added to the ld command from
distribution versions of GCC that enable PIE by default. It is
technically no longer needed after commit c2c81bb2f6 ("RISC-V: Fix the
VDSO symbol generaton for binutils-2.35+"), which removed vdso-dummy.o
in favor of generating vdso-syms.S from vdso.so with $(NM) but this also
resolves the issue in case it ever comes back due to having full control
over the $(LD) command. '-pg' is for function tracing, it is not used
during linking as clang states.
These flags could be removed/filtered to fix the warnings but it is
easier to just match the rest of the kernel and use $(LD) directly for
linking. See commits
fe00e50b2d ("ARM: 8858/1: vdso: use $(LD) instead of $(CC) to link VDSO")
691efbedc6 ("arm64: vdso: use $(LD) instead of $(CC) to link VDSO")
2ff906994b ("MIPS: VDSO: Use $(LD) instead of $(CC) to link VDSO")
2b2a25845d ("s390/vdso: Use $(LD) instead of $(CC) to link vDSO")
for more information.
The flags are converted to linker flags and '--eh-frame-hdr' is added to
match what is added by GCC implicitly, which can be seen by adding '-v'
to GCC's invocation.
Additionally, since this area is being modified, use the $(OBJCOPY)
variable instead of an open coded $(CROSS_COMPILE)objcopy so that the
user's choice of objcopy binary is respected.
Link: https://github.com/ClangBuiltLinux/linux/issues/803
Link: https://github.com/ClangBuiltLinux/linux/issues/970
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Fangrui Song <maskray@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Add sign extension to the $badaddr before addressing the instruction page
fault and instruction access fault to workaround the issue "cip-453".
To avoid affecting the existing code sequence, this patch will creates two
trampolines to add sign extension to the $badaddr. By the "alternative"
mechanism, these two trampolines will replace the original exception
handler of instruction page fault and instruction access fault in the
excp_vect_table. In this case, only the specific SiFive CPU core jumps to
the do_page_fault and do_trap_insn_fault through these two trampolines.
Other CPUs are not affected.
Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Introduce the "alternative" mechanism from ARM64 and x86 to apply the CPU
vendors' errata solution at runtime. The main purpose of this patch is
to provide a framework. Therefore, the implementation is quite basic for
now so that some scenarios could not use this schemei, such as patching
code to a module, relocating the patching code and heterogeneous CPU
topology.
Users could use the macro ALTERNATIVE to apply an errata to the existing
code flow. In the macro ALTERNATIVE, users need to specify the manufacturer
information(vendorid, archid, and impid) for this errata. Therefore, kernel
will know this errata is suitable for which CPU core. During the booting
procedure, kernel will select the errata required by the CPU core and then
patch it. It means that the kernel only applies the errata to the specified
CPU core. In this case, the vendor's errata does not affect each other at
runtime. The above patching procedure only occurs during the booting phase,
so we only take the overhead of the "alternative" mechanism once.
This "alternative" mechanism is enabled by default to ensure that all
required errata will be applied. However, users can disable this feature by
the Kconfig "CONFIG_RISCV_ERRATA_ALTERNATIVE".
Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Add 3 wrapper functions to get vendor id, architecture id and implement id
from M-mode
Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Current riscv's kprobe handlers are run with both preemption and
interrupt enabled, this violates kprobe requirements. Fix this issue
by keeping interrupts disabled for BREAKPOINT exception.
Fixes: c22b0bcb1d ("riscv: Add kprobes supported")
Cc: stable@vger.kernel.org
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
[Palmer: add a comment]
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Currently, the riscv's kprobes(powerred by ftrace) handler is
preemptible. Futher check indicates we miss something similar as the
commit c536aa1c5b ("kprobes/ftrace: Add recursion protection to the
ftrace callback"), so do similar modifications as the commit does.
Fixes: 829adda597 ("riscv: Add KPROBES_ON_FTRACE supported")
Cc: stable@vger.kernel.org
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>