0
0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-12-14 06:24:53 +08:00
Commit Graph

437 Commits

Author SHA1 Message Date
Linus Torvalds
5695e51619 io_uring-worker.v3-2021-02-25
-----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAmA4JRkQHGF4Ym9lQGtl
 cm5lbC5kawAKCRD301j7KXHgpoWqD/9dbbqe8L701U6May1A/4hRsqL4THTA2flx
 vNCNRBl6XV3l/wBCtL6waKy6tyO4lyM8XdUdEvo3Kxl2kGPb8eVfpyYL/+77HqyH
 ctT4RMrs+84Mxn+5N6cM97hS1qVI2moTxxyvOEl/JTB7BYrutz9gvAoeY3/Dto47
 J66oSaPeuqJ32TyihxfQHVxQopJcqFzDjyoYHGDu6ATio1PXfaIdTu8ywVYSECAh
 pWI4rwnqdurGuHMNpxyL1bA6CT/jC7s+sqU7bUYUCgtYI3eG0u3V0bp5gAQQIgl9
 5sxxE3DidYGAkYZsosrelshBtzGddLdz4Qrt2ungMYv8RsGNpFQ095jDPKDwFaZj
 bSvSsfplCo7iFsJByb1TtpNEOW8eAwi81PmBDVQ9Oq5P5ygTYno9GBDc/20ql0Fk
 q6wcX28coE3IBw44ne0hIwvBOtXV4WJyluG/gqOxfbTH+kOy3pDsN8lWcY/P4X0U
 yzdU2MLHe8BNMyYlUiBF47Amzt4ltr85P4XD3WZ4bX71iwri6HvrdGWLuuKwX+Ie
 66QiIDDQIYZQ6NMMJWS9DGW3y3DBizpSXGxONbOw1J2bQdNmtToR0D2UnK/9UnKp
 msnvkUNk8fkYGS4aptpJ6HxbmjMEG5YtbiGlPj6fz5/7MTvhRjPxt7A0LWrUIdqR
 f88+sHUMqg==
 =oc8u
 -----END PGP SIGNATURE-----

Merge tag 'io_uring-worker.v3-2021-02-25' of git://git.kernel.dk/linux-block

Pull io_uring thread rewrite from Jens Axboe:
 "This converts the io-wq workers to be forked off the tasks in question
  instead of being kernel threads that assume various bits of the
  original task identity.

  This kills > 400 lines of code from io_uring/io-wq, and it's the worst
  part of the code. We've had several bugs in this area, and the worry
  is always that we could be missing some pieces for file types doing
  unusual things (recent /dev/tty example comes to mind, userfaultfd
  reads installing file descriptors is another fun one... - both of
  which need special handling, and I bet it's not the last weird oddity
  we'll find).

  With these identical workers, we can have full confidence that we're
  never missing anything. That, in itself, is a huge win. Outside of
  that, it's also more efficient since we're not wasting space and code
  on tracking state, or switching between different states.

  I'm sure we're going to find little things to patch up after this
  series, but testing has been pretty thorough, from the usual
  regression suite to production. Any issue that may crop up should be
  manageable.

  There's also a nice series of further reductions we can do on top of
  this, but I wanted to get the meat of it out sooner rather than later.
  The general worry here isn't that it's fundamentally broken. Most of
  the little issues we've found over the last week have been related to
  just changes in how thread startup/exit is done, since that's the main
  difference between using kthreads and these kinds of threads. In fact,
  if all goes according to plan, I want to get this into the 5.10 and
  5.11 stable branches as well.

  That said, the changes outside of io_uring/io-wq are:

   - arch setup, simple one-liner to each arch copy_thread()
     implementation.

   - Removal of net and proc restrictions for io_uring, they are no
     longer needed or useful"

* tag 'io_uring-worker.v3-2021-02-25' of git://git.kernel.dk/linux-block: (30 commits)
  io-wq: remove now unused IO_WQ_BIT_ERROR
  io_uring: fix SQPOLL thread handling over exec
  io-wq: improve manager/worker handling over exec
  io_uring: ensure SQPOLL startup is triggered before error shutdown
  io-wq: make buffered file write hashed work map per-ctx
  io-wq: fix race around io_worker grabbing
  io-wq: fix races around manager/worker creation and task exit
  io_uring: ensure io-wq context is always destroyed for tasks
  arch: ensure parisc/powerpc handle PF_IO_WORKER in copy_thread()
  io_uring: cleanup ->user usage
  io-wq: remove nr_process accounting
  io_uring: flag new native workers with IORING_FEAT_NATIVE_WORKERS
  net: remove cmsg restriction from io_uring based send/recvmsg calls
  Revert "proc: don't allow async path resolution of /proc/self components"
  Revert "proc: don't allow async path resolution of /proc/thread-self components"
  io_uring: move SQPOLL thread io-wq forked worker
  io-wq: make io_wq_fork_thread() available to other users
  io-wq: only remove worker from free_list, if it was there
  io_uring: remove io_identity
  io_uring: remove any grabbing of context
  ...
2021-02-27 08:29:02 -08:00
Linus Torvalds
8b83369ddc RISC-V Patches for the 5.12 Merge Window
I have 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.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEKzw3R0RoQ7JKlDp6LhMZ81+7GIkFAmA4hXATHHBhbG1lckBk
 YWJiZWx0LmNvbQAKCRAuExnzX7sYifryD/0SfXGOfj93Cxq7I7AYhhzCN7lJ5jvv
 iEQScTlPqU9nfvYodo4EDq0fp+5LIPpTL/XBHtqVjzv0FqRNa28Ea0K7kO8HuXc4
 BaUd0m/DqyB4Gfgm4qjc5bDneQ1ZYxVXprYERWNQ5Fj+tdWhaQGOW64N/TVodjjj
 NgJtTqbIAcjJqjUtttM8TZN5U1TgwLo+KCqw3iYW12lV1YKBBuvrwvSdD6jnFdIQ
 AzG/wRGZhxLoFxgBB/NEsZxDoSd6ztiwxLhS9lX4okZVsryyIdOE70Q/MflfiTlU
 xE+AdxQXTMUiiqYSmHeDD6PDb57GT/K3hnjI1yP+lIZpbInsi29JKow1qjyYjfHl
 9cSSKYCIXHL7jKU6pgt34G1O5N5+fgqHQhNbfKvlrQ2UPlfs/tWdKHpFIP/z9Jlr
 0vCAou7NSEB9zZGqzO63uBLXoN8yfL8FT3uRnnRvoRpfpex5dQX2QqPLQ7327D7N
 GUG31nd1PHTJPdxJ1cI4SO24PqPpWDWY9uaea+0jv7ivGClVadZPco/S3ZKloguT
 lazYUvyA4oRrSAyln785Rd8vg4CinqTxMtIyZbRMbNkgzVQARi9a8rjvu4n9qms2
 2wlXDFi8nR8B4ih5n79dSiiLM9ay9GJDxMcf9VxIxSAYZV2fJALnpK6gV2fzRBUe
 +k/uv8BIsFmlwQ==
 =CutX
 -----END PGP SIGNATURE-----

Merge tag 'riscv-for-linus-5.12-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

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
  ...
2021-02-26 10:28:35 -08:00
Tobias Klauser
f3d60f2a25
riscv: Disable KSAN_SANITIZE for vDSO
We use the generic C VDSO implementations of a handful of clock-related
functions.  When kasan is enabled this results in asan stub calls that
are unlikely to be resolved by userspace, this just disables KASAN
when building the VDSO.

Verified the fix on a kernel with KASAN enabled using vDSO selftests.

Link: https://lore.kernel.org/lkml/CACT4Y+ZNJBnkKHXUf=tm_yuowvZvHwN=0rmJ=7J+xFd+9r_6pQ@mail.gmail.com/
Tested-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Tested-by: Dmitry Vyukov <dvyukov@google.com>
[Palmer: commit text]
Fixes: ad5d1122b8 ("riscv: use vDSO common flow to reduce the latency of the time-related functions")
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-02-22 17:51:23 -08:00
Atish Patra
4bb875632a
RISC-V: Add a non-void return for sbi v02 functions
SBI v0.2 functions can return an error code from SBI implementation.
We are already processing the SBI error code and coverts it to the Linux
error code.

Propagate to the error code to the caller as well. As of now, kvm is the
only user of these error codes.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-02-22 17:51:03 -08:00
Jens Axboe
4727dc20e0 arch: setup PF_IO_WORKER threads like PF_KTHREAD
PF_IO_WORKER are kernel threads too, but they aren't PF_KTHREAD in the
sense that we don't assign ->set_child_tid with our own structure. Just
ensure that every arch sets up the PF_IO_WORKER threads like kthreads
in the arch implementation of copy_thread().

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-02-21 17:25:22 -07:00
Palmer Dabbelt
5dd6713331
RISC-V: probes: Treat the instruction stream as host-endian
Neither of these are actually correct: the instruction stream is defined
(for versions of the ISA manual newer than 2.2) as a stream of 16-bit
little-endian parcels, which is different than just being little-endian.
In theory we should represent this as a type, but we don't have any
concrete plans for the big endian stuff so it doesn't seem worth the
time -- we've got variants of this all over the place.

Instead I'm just dropping the unnecessary type conversion, which is a
NOP on LE systems but causes an sparse error as the types are all mixed
up.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Acked-by: Guo Ren <guoren@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-02-18 23:18:02 -08:00
tangchunyou
5da9cbd2b2
arch/riscv:fix typo in a comment in arch/riscv/kernel/image-vars.h
"kerne" -> "kernel"

Signed-off-by: WenZhang <zhangwen@yulong.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-02-18 23:18:00 -08:00
Vitaly Wool
f105aa940e
riscv: add BUILTIN_DTB support for MMU-enabled targets
Sometimes, especially in a production system we may not want to
use a "smart bootloader" like u-boot to load kernel, ramdisk and
device tree from a filesystem on eMMC, but rather load the kernel
from a NAND partition and just run it as soon as we can, and in
this case it is convenient to have device tree compiled into the
kernel binary. Since this case is not limited to MMU-less systems,
let's support it for these which have MMU enabled too.

While at it, provide __dtb_start as a parameter to setup_vm() in
BUILTIN_DTB case, so we don't have to duplicate BUILTIN_DTB specific
processing in MMU-enabled and MMU-disabled versions of setup_vm().

Signed-off-by: Vitaly Wool <vitaly.wool@konsulko.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-02-18 23:17:54 -08:00
Atish Patra
f105ea9890
RISC-V: Fix .init section permission update
.init section permission should only updated to non-execute if
STRICT_KERNEL_RWX is enabled. Otherwise, this will lead to a kernel hang.

Fixes: 19a0086902 ("RISC-V: Protect all kernel sections including init early")
Cc: stable@vger.kernel.org
Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-02-02 18:35:42 -08:00
Atish Patra
797f0375dd
RISC-V: Do not allocate memblock while iterating reserved memblocks
Currently, resource tree allocates memory blocks while iterating on the
list. It leads to following kernel warning because memblock allocation
also invokes memory block reservation API.

[    0.000000] ------------[ cut here ]------------
[    0.000000] WARNING: CPU: 0 PID: 0 at kernel/resource.c:795
__insert_resource+0x8e/0xd0
[    0.000000] Modules linked in:
[    0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted
5.10.0-00022-ge20097fb37e2-dirty 
[    0.000000] epc: c00125c2 ra : c001262c sp : c1c01f50
[    0.000000]  gp : c1d456e0 tp : c1c0a980 t0 : ffffcf20
[    0.000000]  t1 : 00000000 t2 : 00000000 s0 : c1c01f60
[    0.000000]  s1 : ffffcf00 a0 : ffffff00 a1 : c1c0c0c4
[    0.000000]  a2 : 80c12b15 a3 : 80402000 a4 : 80402000
[    0.000000]  a5 : c1c0c0c4 a6 : 80c12b15 a7 : f5faf600
[    0.000000]  s2 : c1c0c0c4 s3 : c1c0e000 s4 : c1009a80
[    0.000000]  s5 : c1c0c000 s6 : c1d48000 s7 : c1613b4c
[    0.000000]  s8 : 00000fff s9 : 80000200 s10: c1613b40
[    0.000000]  s11: 00000000 t3 : c1d4a000 t4 : ffffffff

This is also unnecessary as we can pre-compute the total memblocks required
for each memory region and allocate it before the loop. It save precious
boot time not going through memblock allocation code every time.

Fixes: 00ab027a3b ("RISC-V: Add kernel image sections to the resource tree")

Reviewed-by: Anup Patel <anup@brainfault.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-15 21:35:46 -08:00
Kefeng Wang
dec822771b
riscv: stacktrace: Move register keyword to beginning of declaration
Using global sp_in_global directly to fix the following warning,

arch/riscv/kernel/stacktrace.c:31:3: warning: ‘register’ is not at beginning of declaration [-Wold-style-declaration]
31 |   const register unsigned long current_sp = sp_in_global;
   |   ^~~~~

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14 18:31:47 -08:00
Chen Huang
f766f77a74
riscv/stacktrace: Fix stack output without ra on the stack top
When a function doesn't have a callee, then it will not
push ra into the stack, such as lkdtm_BUG() function,

addi	sp,sp,-16
sd	s0,8(sp)
addi	s0,sp,16
ebreak

The struct stackframe use {fp,ra} to get information from
stack, if walk_stackframe() with pr_regs, we will obtain
wrong value and bad stacktrace,

[<ffffffe00066c56c>] lkdtm_BUG+0x6/0x8
---[ end trace 18da3fbdf08e25d5 ]---

Correct the next fp and pc, after that, full stacktrace
shown as expects,

[<ffffffe00066c56c>] lkdtm_BUG+0x6/0x8
[<ffffffe0008b24a4>] lkdtm_do_action+0x14/0x1c
[<ffffffe00066c372>] direct_entry+0xc0/0x10a
[<ffffffe000439f86>] full_proxy_write+0x42/0x6a
[<ffffffe000309626>] vfs_write+0x7e/0x214
[<ffffffe00030992a>] ksys_write+0x98/0xc0
[<ffffffe000309960>] sys_write+0xe/0x16
[<ffffffe0002014bc>] ret_from_syscall+0x0/0x2
---[ end trace 61917f3d9a9fadcd ]---

Signed-off-by: Chen Huang <chenhuang5@huawei.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14 15:09:13 -08:00
Kefeng Wang
da401e8945
riscv: Improve __show_regs
Show the function symbols of epc and ra to improve the
readability of crash reports, and align the printing
formats about the raw epc value.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14 15:09:12 -08:00
Kefeng Wang
091b945085
riscv: Add dump stack in show_regs
Like commit 1149aad10b ("arm64: Add dump_backtrace() in show_regs"),
dump the stack in riscv show_regs as common code expects.

Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14 15:09:11 -08:00
Guo Ren
fea2fed201
riscv: Enable per-task stack canaries
This enables the use of per-task stack canary values if GCC has
support for emitting the stack canary reference relative to the
value of tp, which holds the task struct pointer in the riscv
kernel.

After compare arm64 and x86 implementations, seems arm64's is more
flexible and readable. The key point is how gcc get the offset of
stack_canary from gs/el0_sp.

x86: Use a fix offset from gs, not flexible.

struct fixed_percpu_data {
	/*
	 * GCC hardcodes the stack canary as %gs:40.  Since the
	 * irq_stack is the object at %gs:0, we reserve the bottom
	 * 48 bytes of the irq stack for the canary.
	 */
	char            gs_base[40]; // :(
	unsigned long   stack_canary;
};

arm64: Use -mstack-protector-guard-offset & guard-reg
	gcc options:
	-mstack-protector-guard=sysreg
	-mstack-protector-guard-reg=sp_el0
	-mstack-protector-guard-offset=xxx

riscv: Use -mstack-protector-guard-offset & guard-reg
	gcc options:
	-mstack-protector-guard=tls
	-mstack-protector-guard-reg=tp
	-mstack-protector-guard-offset=xxx

 GCC's implementation has been merged:
 commit c931e8d5a96463427040b0d11f9c4352ac22b2b0
 Author: Cooper Qu <cooper.qu@linux.alibaba.com>
 Date:   Mon Jul 13 16:15:08 2020 +0800

     RISC-V: Add support for TLS stack protector canary access

In the end, these codes are inserted by gcc before return:

*  0xffffffe00020b396 <+120>:   ld      a5,1008(tp) # 0x3f0
*  0xffffffe00020b39a <+124>:   xor     a5,a5,a4
*  0xffffffe00020b39c <+126>:   mv      a0,s5
*  0xffffffe00020b39e <+128>:   bnez    a5,0xffffffe00020b61c <_do_fork+766>
   0xffffffe00020b3a2 <+132>:   ld      ra,136(sp)
   0xffffffe00020b3a4 <+134>:   ld      s0,128(sp)
   0xffffffe00020b3a6 <+136>:   ld      s1,120(sp)
   0xffffffe00020b3a8 <+138>:   ld      s2,112(sp)
   0xffffffe00020b3aa <+140>:   ld      s3,104(sp)
   0xffffffe00020b3ac <+142>:   ld      s4,96(sp)
   0xffffffe00020b3ae <+144>:   ld      s5,88(sp)
   0xffffffe00020b3b0 <+146>:   ld      s6,80(sp)
   0xffffffe00020b3b2 <+148>:   ld      s7,72(sp)
   0xffffffe00020b3b4 <+150>:   addi    sp,sp,144
   0xffffffe00020b3b6 <+152>:   ret
   ...
*  0xffffffe00020b61c <+766>:   auipc   ra,0x7f8
*  0xffffffe00020b620 <+770>:   jalr    -1764(ra) # 0xffffffe000a02f38 <__stack_chk_fail>

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Signed-off-by: Cooper Qu <cooper.qu@linux.alibaba.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14 15:09:10 -08:00
Guo Ren
74784081aa
riscv: Add uprobes supported
This patch adds support for uprobes on riscv architecture.

Just like kprobe, it support single-step and simulate instructions.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14 15:09:08 -08:00
Guo Ren
829adda597
riscv: Add KPROBES_ON_FTRACE supported
This patch adds support for kprobes on ftrace call sites to avoids
much of the overhead with regular kprobes. Try it with simple
steps:

 echo 'p:myprobe sys_clone a0=%a0 a1=%a1 stack_val=+4($stack)' > /sys/kernel/de
bug/tracing/kprobe_events
 echo 1 > /sys/kernel/debug/tracing/events/kprobes/enable
 cat /sys/kernel/debug/tracing/trace
 tracer: nop

 entries-in-buffer/entries-written: 1/1   #P:1

                                _-----=> irqs-off
                               / _----=> need-resched
                              | / _---=> hardirq/softirq
                              || / _--=> preempt-depth
                              ||| /     delay
           TASK-PID     CPU#  ||||   TIMESTAMP  FUNCTION
              | |         |   ||||      |         |
              sh-92      [000] ....   369.899962: myprobe: (sys_clone+0x0/0x28) a0=0x1200011 a1=0x0 stack_val=0x201c20ffffffe0
 cat /sys/kernel/debug/kprobes/list
ffffffe00020b584  k  sys_clone+0x0    [FTRACE]
                                       ^^^^^^

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14 15:09:07 -08:00
Guo Ren
c22b0bcb1d
riscv: Add kprobes supported
This patch enables "kprobe & kretprobe" to work with ftrace
interface. It utilized software breakpoint as single-step
mechanism.

Some instructions which can't be single-step executed must be
simulated in kernel execution slot, such as: branch, jal, auipc,
la ...

Some instructions should be rejected for probing and we use a
blacklist to filter, such as: ecall, ebreak, ...

We use ebreak & c.ebreak to replace origin instruction and the
kprobe handler prepares an executable memory slot for out-of-line
execution with a copy of the original instruction being probed.
In execution slot we add ebreak behind original instruction to
simulate a single-setp mechanism.

The patch is based on packi's work [1] and csky's work [2].
 - The kprobes_trampoline.S is all from packi's patch
 - The single-step mechanism is new designed for riscv without hw
   single-step trap
 - The simulation codes are from csky
 - Frankly, all codes refer to other archs' implementation

 [1] https://lore.kernel.org/linux-riscv/20181113195804.22825-1-me@packi.ch/
 [2] https://lore.kernel.org/linux-csky/20200403044150.20562-9-guoren@kernel.org/

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Co-developed-by: Patrick Stählin <me@packi.ch>
Signed-off-by: Patrick Stählin <me@packi.ch>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Zong Li <zong.li@sifive.com>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Cc: Patrick Stählin <me@packi.ch>
Cc: Palmer Dabbelt <palmerdabbelt@google.com>
Cc: Björn Töpel <bjorn.topel@gmail.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14 15:09:06 -08:00
Guo Ren
afc76b8b80
riscv: Using PATCHABLE_FUNCTION_ENTRY instead of MCOUNT
This patch changes the current detour mechanism of dynamic ftrace
which has been discussed during LPC 2020 RISCV-MC [1].

Before the patch, we used mcount for detour:
<funca>:
	addi sp,sp,-16
	sd   ra,8(sp)
	sd   s0,0(sp)
	addi s0,sp,16
	mv   a5,ra
	mv   a0,a5
	auipc ra,0x0 -> nop
	jalr  -296(ra) <_mcount@plt> ->nop
	...

After the patch, we use nop call site area for detour:
<funca>:
	nop -> REG_S ra, -SZREG(sp)
	nop -> auipc ra, 0x?
	nop -> jalr ?(ra)
	nop -> REG_L ra, -SZREG(sp)
	...

The mcount mechanism is mixed with gcc function prologue which is
not very clear. The patchable function entry just put 16 bytes nop
before the front of the function prologue which could be filled
with a separated detour mechanism.

[1] https://www.linuxplumbersconf.org/event/7/contributions/807/

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14 15:09:05 -08:00
Guo Ren
5ad84adf54
riscv: Fixup patch_text panic in ftrace
Just like arm64, we can't trace the function in the patch_text path.

Here is the bug log:

[   45.234334] Unable to handle kernel paging request at virtual address ffffffd38ae80900
[   45.242313] Oops []
[   45.244600] Modules linked in:
[   45.247678] CPU: 0 PID: 11 Comm: migration/0 Not tainted 5.9.0-00025-g9b7db83-dirty 
[   45.255797] epc: ffffffe00021689a ra : ffffffe00021718e sp : ffffffe01afabb58
[   45.262955]  gp : ffffffe00136afa0 tp : ffffffe01af94d00 t0 : 0000000000000002
[   45.270200]  t1 : 0000000000000000 t2 : 0000000000000001 s0 : ffffffe01afabc08
[   45.277443]  s1 : ffffffe0013718a8 a0 : 0000000000000000 a1 : ffffffe01afabba8
[   45.284686]  a2 : 0000000000000000 a3 : 0000000000000000 a4 : c4c16ad38ae80900
[   45.291929]  a5 : 0000000000000000 a6 : 0000000000000000 a7 : 0000000052464e43
[   45.299173]  s2 : 0000000000000001 s3 : ffffffe000206a60 s4 : ffffffe000206a60
[   45.306415]  s5 : 00000000000009ec s6 : ffffffe0013718a8 s7 : c4c16ad38ae80900
[   45.313658]  s8 : 0000000000000004 s9 : 0000000000000001 s10: 0000000000000001
[   45.320902]  s11: 0000000000000003 t3 : 0000000000000001 t4 : ffffffffd192fe79
[   45.328144]  t5 : ffffffffb8f80000 t6 : 0000000000040000
[   45.333472] status: 0000000200000100 badaddr: ffffffd38ae80900 cause: 000000000000000f
[   45.341514] ---[ end trace d95102172248fdcf ]---
[   45.346176] note: migration/0[11] exited with preempt_count 1

(gdb) x /2i $pc
=> 0xffffffe00021689a <__do_proc_dointvec+196>: sd      zero,0(s7)
   0xffffffe00021689e <__do_proc_dointvec+200>: li      s11,0

(gdb) bt
0  __do_proc_dointvec (tbl_data=0x0, table=0xffffffe01afabba8,
write=0, buffer=0x0, lenp=0x7bf897061f9a0800, ppos=0x4, conv=0x0,
data=0x52464e43) at kernel/sysctl.c:581
1  0xffffffe00021718e in do_proc_dointvec (data=<optimized out>,
conv=<optimized out>, ppos=<optimized out>, lenp=<optimized out>,
buffer=<optimized out>, write=<optimized out>, table=<optimized out>)
at kernel/sysctl.c:964
2  proc_dointvec_minmax (ppos=<optimized out>, lenp=<optimized out>,
buffer=<optimized out>, write=<optimized out>, table=<optimized out>)
at kernel/sysctl.c:964
3  proc_do_static_key (table=<optimized out>, write=1, buffer=0x0,
lenp=0x0, ppos=0x7bf897061f9a0800) at kernel/sysctl.c:1643
4  0xffffffe000206792 in ftrace_make_call (rec=<optimized out>,
addr=<optimized out>) at arch/riscv/kernel/ftrace.c:109
5  0xffffffe0002c9c04 in __ftrace_replace_code
(rec=0xffffffe01ae40c30, enable=3) at kernel/trace/ftrace.c:2503
6  0xffffffe0002ca0b2 in ftrace_replace_code (mod_flags=<optimized
out>) at kernel/trace/ftrace.c:2530
7  0xffffffe0002ca26a in ftrace_modify_all_code (command=5) at
kernel/trace/ftrace.c:2677
8  0xffffffe0002ca30e in __ftrace_modify_code (data=<optimized out>)
at kernel/trace/ftrace.c:2703
9  0xffffffe0002c13b0 in multi_cpu_stop (data=0x0) at kernel/stop_machine.c:224
10 0xffffffe0002c0fde in cpu_stopper_thread (cpu=<optimized out>) at
kernel/stop_machine.c:491
11 0xffffffe0002343de in smpboot_thread_fn (data=0x0) at kernel/smpboot.c:165
12 0xffffffe00022f8b4 in kthread (_create=0xffffffe01af0c040) at
kernel/kthread.c:292
13 0xffffffe000201fac in handle_exception () at arch/riscv/kernel/entry.S:236

   0xffffffe00020678a <+114>:   auipc   ra,0xffffe
   0xffffffe00020678e <+118>:   jalr    -118(ra) # 0xffffffe000204714 <patch_text_nosync>
   0xffffffe000206792 <+122>:   snez    a0,a0

(gdb) disassemble patch_text_nosync
Dump of assembler code for function patch_text_nosync:
   0xffffffe000204714 <+0>:     addi    sp,sp,-32
   0xffffffe000204716 <+2>:     sd      s0,16(sp)
   0xffffffe000204718 <+4>:     sd      ra,24(sp)
   0xffffffe00020471a <+6>:     addi    s0,sp,32
   0xffffffe00020471c <+8>:     auipc   ra,0x0
   0xffffffe000204720 <+12>:    jalr    -384(ra) # 0xffffffe00020459c <patch_insn_write>
   0xffffffe000204724 <+16>:    beqz    a0,0xffffffe00020472e <patch_text_nosync+26>
   0xffffffe000204726 <+18>:    ld      ra,24(sp)
   0xffffffe000204728 <+20>:    ld      s0,16(sp)
   0xffffffe00020472a <+22>:    addi    sp,sp,32
   0xffffffe00020472c <+24>:    ret
   0xffffffe00020472e <+26>:    sd      a0,-24(s0)
   0xffffffe000204732 <+30>:    auipc   ra,0x4
   0xffffffe000204736 <+34>:    jalr    -1464(ra) # 0xffffffe00020817a <flush_icache_all>
   0xffffffe00020473a <+38>:    ld      a0,-24(s0)
   0xffffffe00020473e <+42>:    ld      ra,24(sp)
   0xffffffe000204740 <+44>:    ld      s0,16(sp)
   0xffffffe000204742 <+46>:    addi    sp,sp,32
   0xffffffe000204744 <+48>:    ret

(gdb) disassemble flush_icache_all-4
Dump of assembler code for function flush_icache_all:
   0xffffffe00020817a <+0>:     addi    sp,sp,-8
   0xffffffe00020817c <+2>:     sd      ra,0(sp)
   0xffffffe00020817e <+4>:     auipc   ra,0xfffff
   0xffffffe000208182 <+8>:     jalr    -1822(ra) # 0xffffffe000206a60 <ftrace_caller>
   0xffffffe000208186 <+12>:    ld      ra,0(sp)
   0xffffffe000208188 <+14>:    addi    sp,sp,8
   0xffffffe00020818a <+0>:     addi    sp,sp,-16
   0xffffffe00020818c <+2>:     sd      s0,0(sp)
   0xffffffe00020818e <+4>:     sd      ra,8(sp)
   0xffffffe000208190 <+6>:     addi    s0,sp,16
   0xffffffe000208192 <+8>:     li      a0,0
   0xffffffe000208194 <+10>:    auipc   ra,0xfffff
   0xffffffe000208198 <+14>:    jalr    -410(ra) # 0xffffffe000206ffa <sbi_remote_fence_i>
   0xffffffe00020819c <+18>:    ld      s0,0(sp)
   0xffffffe00020819e <+20>:    ld      ra,8(sp)
   0xffffffe0002081a0 <+22>:    addi    sp,sp,16
   0xffffffe0002081a2 <+24>:    ret

(gdb) frame 5
(rec=0xffffffe01ae40c30, enable=3) at kernel/trace/ftrace.c:2503
2503                    return ftrace_make_call(rec, ftrace_addr);
(gdb) p /x rec->ip
$2 = 0xffffffe00020817a -> flush_icache_all !

When we modified flush_icache_all's patchable-entry with ftrace_caller:
 - Insert ftrace_caller at flush_icache_all prologue.
 - Call flush_icache_all to sync I/Dcache, but flush_icache_all is
just we modified by half.

Link: https://lore.kernel.org/linux-riscv/CAJF2gTT=oDWesWe0JVWvTpGi60-gpbNhYLdFWN_5EbyeqoEDdw@mail.gmail.com/T/#t
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14 15:09:04 -08:00
Guo Ren
67d9457780
riscv: Fixup wrong ftrace remove cflag
We must use $(CC_FLAGS_FTRACE) instead of directly using -pg. It
will cause -fpatchable-function-entry error.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14 15:09:03 -08:00
Guo Ren
edfcf91fe4
riscv: Fixup compile error BUILD_BUG_ON failed
Unfortunately, the current code couldn't be compiled:

  CC      arch/riscv/kernel/patch.o
In file included from ./include/linux/kernel.h:11,
                 from ./include/linux/list.h:9,
                 from ./include/linux/preempt.h:11,
                 from ./include/linux/spinlock.h:51,
                 from arch/riscv/kernel/patch.c:6:
In function ‘fix_to_virt’,
    inlined from ‘patch_map’ at arch/riscv/kernel/patch.c:37:17:
./include/linux/compiler.h:392:38: error: call to ‘__compiletime_assert_205’ declared with attribute error: BUILD_BUG_ON failed: idx >= __end_of_fixed_addresses
  _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
                                      ^
./include/linux/compiler.h:373:4: note: in definition of macro ‘__compiletime_assert’
    prefix ## suffix();    \
    ^~~~~~
./include/linux/compiler.h:392:2: note: in expansion of macro ‘_compiletime_assert’
  _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
  ^~~~~~~~~~~~~~~~~~~
./include/linux/build_bug.h:39:37: note: in expansion of macro ‘compiletime_assert’
 #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
                                     ^~~~~~~~~~~~~~~~~~
./include/linux/build_bug.h:50:2: note: in expansion of macro ‘BUILD_BUG_ON_MSG’
  BUILD_BUG_ON_MSG(condition, "BUILD_BUG_ON failed: " #condition)
  ^~~~~~~~~~~~~~~~
./include/asm-generic/fixmap.h:32:2: note: in expansion of macro ‘BUILD_BUG_ON’
  BUILD_BUG_ON(idx >= __end_of_fixed_addresses);
  ^~~~~~~~~~~~

Because fix_to_virt(, idx) needs a const value, not a dynamic variable of
reg-a0 or BUILD_BUG_ON failed with "idx >= __end_of_fixed_addresses".

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14 15:09:01 -08:00
Patrick Stählin
dcdc7a53a8
RISC-V: Implement ptrace regs and stack API
Needed for kprobes support. Copied and adapted from arm64 code.

Guo Ren fixup pt_regs type for linux-5.8-rc1.

Signed-off-by: Patrick Stählin <me@packi.ch>
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Reviewed-by: Zong Li <zong.li@sifive.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14 15:09:01 -08:00
Kefeng Wang
46ad48e8a2
riscv: Add machine name to kernel boot log and stack dump output
Add the machine name to kernel boot-up log, and install
the machine name to stack dump for DT boot mode.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14 15:08:59 -08:00
Atish Patra
4f0e8eef77
riscv: Add numa support for riscv64 platform
Use the generic numa implementation to add NUMA support for RISC-V.
This is based on Greentime's patch[1] but modified to use generic NUMA
implementation and few more fixes.

[1] https://lkml.org/lkml/2020/1/10/233

Co-developed-by: Greentime Hu <greentime.hu@sifive.com>
Signed-off-by: Greentime Hu <greentime.hu@sifive.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14 15:08:58 -08:00
Atish Patra
cbd34f4bb3
riscv: Separate memory init from paging init
Currently, we perform some memory init functions in paging init. But,
that will be an issue for NUMA support where DT needs to be flattened
before numa initialization and memblock_present can only be called
after numa initialization.

Move memory initialization related functions to a separate function.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Greentime Hu <greentime.hu@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14 15:08:56 -08:00
Guo Ren
0aa2ec8a47
riscv: Fixup CONFIG_GENERIC_TIME_VSYSCALL
The patch fix commit: ad5d112 ("riscv: use vDSO common flow to
reduce the latency of the time-related functions").

The GENERIC_TIME_VSYSCALL should be CONFIG_GENERIC_TIME_VSYSCALL
or vgettimeofday won't work.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Fixes: ad5d1122b8 ("riscv: use vDSO common flow to reduce the latency of the time-related functions")
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-12 20:34:44 -08:00
Kefeng Wang
80709af732
riscv: cacheinfo: Fix using smp_processor_id() in preemptible
Use raw_smp_processor_id instead of smp_processor_id() to fix warning,

BUG: using smp_processor_id() in preemptible [00000000] code: init/1
caller is debug_smp_processor_id+0x1c/0x26
CPU: 0 PID: 1 Comm: init Not tainted 5.10.0-rc4 
Call Trace:
  walk_stackframe+0x0/0xaa
  show_stack+0x32/0x3e
  dump_stack+0x76/0x90
  check_preemption_disabled+0xaa/0xac
  debug_smp_processor_id+0x1c/0x26
  get_cache_size+0x18/0x68
  load_elf_binary+0x868/0xece
  bprm_execve+0x224/0x498
  kernel_execve+0xdc/0x142
  run_init_process+0x90/0x9e
  try_to_run_init_process+0x12/0x3c
  kernel_init+0xb4/0xf8
  ret_from_exception+0x0/0xc

The issue is found when CONFIG_DEBUG_PREEMPT enabled.

Reviewed-by: Atish Patra <atish.patra@wdc.com>
Tested-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
[Palmer: Added a comment.]
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-12 20:25:32 -08:00
Atish Patra
7cd1af107a
riscv: Trace irq on only interrupt is enabled
We should call irq trace only if interrupt is going to be enabled during
excecption handling. Otherwise, it results in following warning during
boot with lock debugging enabled.

[    0.000000] ------------[ cut here ]------------
[    0.000000] DEBUG_LOCKS_WARN_ON(early_boot_irqs_disabled)
[    0.000000] WARNING: CPU: 0 PID: 0 at kernel/locking/lockdep.c:4085 lockdep_hardirqs_on_prepare+0x22a/0x22e
[    0.000000] Modules linked in:
[    0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 5.10.0-00022-ge20097fb37e2-dirty 
[    0.000000] epc: c005d5d4 ra : c005d5d4 sp : c1c01e80
[    0.000000]  gp : c1d456e0 tp : c1c0a980 t0 : 00000000
[    0.000000]  t1 : ffffffff t2 : 00000000 s0 : c1c01ea0
[    0.000000]  s1 : c100f360 a0 : 0000002d a1 : c00666ee
[    0.000000]  a2 : 00000000 a3 : 00000000 a4 : 00000000
[    0.000000]  a5 : 00000000 a6 : c1c6b390 a7 : 3ffff00e
[    0.000000]  s2 : c2384fe8 s3 : 00000000 s4 : 00000001
[    0.000000]  s5 : c1c0a980 s6 : c1d48000 s7 : c1613b4c
[    0.000000]  s8 : 00000fff s9 : 80000200 s10: c1613b40
[    0.000000]  s11: 00000000 t3 : 00000000 t4 : 00000000
[    0.000000]  t5 : 00000001 t6 : 00000000

Fixes: 3c46979829 ("riscv:Enable LOCKDEP_SUPPORT & fixup TRACE_IRQFLAGS_SUPPORT")

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-12 20:16:35 -08:00
Damien Le Moal
d5805af9fe
riscv: Fix builtin DTB handling
All SiPeed K210 MAIX boards have the exact same vendor, arch and
implementation IDs, preventing differentiation to select the correct
device tree to use through the SOC_BUILTIN_DTB_DECLARE() macro. This
result in this macro to be useless and mandates changing the code of
the sysctl driver to change the builtin device tree suitable for the
target board.

Fix this problem by removing the SOC_BUILTIN_DTB_DECLARE() macro since
it is used only for the K210 support. The code searching the builtin
DTBs using the vendor, arch an implementation IDs is also removed.
Support for builtin DTB falls back to the simpler and more traditional
handling of builtin DTB using the CONFIG_BUILTIN_DTB option, similarly
to other architectures.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-07 19:00:50 -08:00
Damien Le Moal
643437b996
riscv: Enable interrupts during syscalls with M-Mode
When running is M-Mode (no MMU config), MPIE does not get set. This
results in all syscalls being executed with interrupts disabled as
handle_exception never sets SR_IE as it always sees SR_PIE being
cleared. Fix this by always force enabling interrupts in
handle_syscall when CONFIG_RISCV_M_MODE is enabled.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-07 18:04:25 -08:00
Damien Le Moal
11f4c2e940
riscv: Fix kernel time_init()
If of_clk_init() is not called in time_init(), clock providers defined
in the system device tree are not initialized, resulting in failures for
other devices to initialize due to missing clocks.
Similarly to other architectures and to the default kernel time_init()
implementation, call of_clk_init() before executing timer_probe() in
time_init().

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-07 18:01:36 -08:00
Andreas Schwab
cf7b2ae4d7
riscv: return -ENOSYS for syscall -1
Properly return -ENOSYS for syscall -1 instead of leaving the return value
uninitialized.  This fixes the strace teststuite.

Fixes: 5340627e3f ("riscv: add support for SECCOMP and SECCOMP_FILTER")
Cc: stable@vger.kernel.org
Signed-off-by: Andreas Schwab <schwab@suse.de>
Reviewed-by: Tycho Andersen <tycho@tycho.pizza>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-07 18:01:34 -08:00
Kefeng Wang
641e8cd2cb
riscv: Cleanup sbi function stubs when RISCV_SBI disabled
Fix sbi_init() function declaration mismatch between RISCV_SBI
enable and disable, as it always returned 0, make it void function.

Drop some stubs which won't be used if RISCV_SBI disabled.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-07 17:19:17 -08:00
Linus Torvalds
e2ae634014 RISC-V Patches for the 5.11 Merge Window, Part 1
We have a handful of new kernel features for 5.11:
 
 * Support for the contiguous memory allocator.
 * Support for IRQ Time Accounting
 * Support for stack tracing
 * Support for strict /dev/mem
 * Support for kernel section protection
 
 I'm being a bit conservative on the cutoff for this round due to the
 timing, so this is all the new development I'm going to take for this
 cycle (even if some of it probably normally would have been OK).  There
 are, however, some fixes on the list that I will likely be sending along
 either later this week or early next week.
 
 There is one issue in here: one of my test configurations
 (PREEMPT{,_DEBUG}=y) fails to boot on QEMU 5.0.0 (from April) as of the
 .text.init alignment patch.  With any luck we'll sort out the issue, but
 given how many bugs get fixed all over the place and how unrelated those
 features seem my guess is that we're just running into something that's
 been lurking for a while and has already been fixed in the newer QEMU
 (though I wouldn't be surprised if it's one of these implicit
 assumptions we have in the boot flow).  If it was hardware I'd be
 strongly inclined to look more closely, but given that users can upgrade
 their simulators I'm less worried about it.
 
 There are two merge conflicts, both in build files.  They're both a bit
 clunky: arch/riscv/Kconfig is out of order (I have a script that's
 supposed to keep them in order, I'll fix it) and lib/Makefile is out of
 order (though GENERIC_LIB here doesn't mean quite what it does above).
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEKzw3R0RoQ7JKlDp6LhMZ81+7GIkFAl/cHO4THHBhbG1lckBk
 YWJiZWx0LmNvbQAKCRAuExnzX7sYiTlmD/4uDyNHBM1XH/XD4fSEwTYJvGLqt/Jo
 vtrGR/fm0SlQFUKCcywSzxcVAeGn56CACbEIDYLuL4xXRJmbwEuaRrHVx2sEhS9p
 pNhy+wus/SgDz5EUAawMyR2AEWgzl77hY5T/+AAo4yv65SGGBfsIdz5noIVwGNqW
 r0g5cw2O99z0vwu1aSrK4isWHconG9MfQnnVyepPSh67pyWS4aUCr1K3vLiqD2dE
 XcgtwdcgzUIY5aEoJNrWo5qTrcaG8m6MRNCDAKJ6MKdDA2wdGIN868G0wQnoURRm
 Y+yW7w3P20kM0b87zH50jujTWg38NBKOfaXb0mAfawZMapL60veTVmvs2kNtFXCy
 F6JWRkgTiRnGY72FtRR0igWXT5M7fz0EiLFXLMItGcgj79TUget4l/3sRMN47S/O
 cA/WiwptJH3mh8IkL6z5ZxWEThdOrbFt8F1T+Gyq/ayblcPnJaLn/wrWoeOwviWR
 fvEC7smuF5SBTbWZK5tBOP21Nvhb7bfr49Sgr8Tvdjl15tz97qK+2tsLXwkBoQnJ
 wU45jcXfzr5wgiGBOQANRite5bLsJ0TuOrTgA5gsGpv+JSDGbpcJbm0833x00nX/
 3GsW5xr+vsLCvljgPAtKsyDNRlGQu908Gxrat2+s8u92bLr1bwn30uKL5h6i/n1w
 QgWATuPPGXZZdw==
 =GWIH
 -----END PGP SIGNATURE-----

Merge tag 'riscv-for-linus-5.11-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 kernel features for 5.11:

   - Support for the contiguous memory allocator.

   - Support for IRQ Time Accounting

   - Support for stack tracing

   - Support for strict /dev/mem

   - Support for kernel section protection

  I'm being a bit conservative on the cutoff for this round due to the
  timing, so this is all the new development I'm going to take for this
  cycle (even if some of it probably normally would have been OK). There
  are, however, some fixes on the list that I will likely be sending
  along either later this week or early next week.

  There is one issue in here: one of my test configurations
  (PREEMPT{,_DEBUG}=y) fails to boot on QEMU 5.0.0 (from April) as of
  the .text.init alignment patch.

  With any luck we'll sort out the issue, but given how many bugs get
  fixed all over the place and how unrelated those features seem my
  guess is that we're just running into something that's been lurking
  for a while and has already been fixed in the newer QEMU (though I
  wouldn't be surprised if it's one of these implicit assumptions we
  have in the boot flow). If it was hardware I'd be strongly inclined to
  look more closely, but given that users can upgrade their simulators
  I'm less worried about it"

* tag 'riscv-for-linus-5.11-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  arm64: Use the generic devmem_is_allowed()
  arm: Use the generic devmem_is_allowed()
  RISC-V: Use the new generic devmem_is_allowed()
  lib: Add a generic version of devmem_is_allowed()
  riscv: Fixed kernel test robot warning
  riscv: kernel: Drop unused clean rule
  riscv: provide memmove implementation
  RISC-V: Move dynamic relocation section under __init
  RISC-V: Protect all kernel sections including init early
  RISC-V: Align the .init.text section
  RISC-V: Initialize SBI early
  riscv: Enable ARCH_STACKWALK
  riscv: Make stack walk callback consistent with generic code
  riscv: Cleanup stacktrace
  riscv: Add HAVE_IRQ_TIME_ACCOUNTING
  riscv: Enable CMA support
  riscv: Ignore Image.* and loader.bin
  riscv: Clean up boot dir
  riscv: Fix compressed Image formats build
  RISC-V: Add kernel image sections to the resource tree
2020-12-18 10:43:07 -08:00
Linus Torvalds
005b2a9dc8 tif-task_work.arch-2020-12-14
-----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAl/YJxsQHGF4Ym9lQGtl
 cm5lbC5kawAKCRD301j7KXHgpjpyEACBdW+YjenjTbkUPeEXzQgkBkTZUYw3g007
 DPcUT1g8PQZXYXlQvBKCvGhhIr7/KVcjepKoowiNQfBNGcIPJTVopW58nzpqAfTQ
 goI2WYGn5EKFFKBPvtH04cJD/Wo8muXdxynKtqyZbnGGgZjQxPrE259b8dpHjBSR
 6L7HHkk0D1oU/5b6h6Ocpg9mc/0iIUCZylySAYY3eGO0JaVPJaXgZSJZYgHxCHll
 Lb+/y/fXdtm/0PmQ3ko0ev54g3yEWqZIX0NsZW1asrButIy+KLzQ2Mz1xFLFDMag
 prtIfwb8tzgc4dFPY090C/azjCh5CPpxqYS6FkRwS0p86n6OhkyXrqfily5Hs4/B
 NC7CBPBSH/j+NKUK7CYZcpTzTpxPjUr9p0anUdlvMJz8FhTb/3YEEZ1UTeWOeHmk
 Yo5SxnFghLeZZeZ1ok6rdymnVa7WEX12SCLGQX31BB2mld0tNbKb4b+FsBF6OUMk
 IUaX6OjwDFVRaysC88BQ4hjcIP1HxsViG4/VZDX15gjAAH2Pvb+7tev+lcDcOhjz
 TCD4GNFspTFzRhh9nT7oxQ679qCh9G9zHbzuIRewnrS6iqvo5SJQB3dR2yrWZRRH
 ySkQFiHpYOlnLJYv0jg9COlGwo2FUdcvKhCvkjQKKBz48rzW/IC0LwKdRQWZDFk3
 FKGzP/NBig==
 =cadT
 -----END PGP SIGNATURE-----

Merge tag 'tif-task_work.arch-2020-12-14' of git://git.kernel.dk/linux-block

Pull TIF_NOTIFY_SIGNAL updates from Jens Axboe:
 "This sits on top of of the core entry/exit and x86 entry branch from
  the tip tree, which contains the generic and x86 parts of this work.

  Here we convert the rest of the archs to support TIF_NOTIFY_SIGNAL.

  With that done, we can get rid of JOBCTL_TASK_WORK from task_work and
  signal.c, and also remove a deadlock work-around in io_uring around
  knowing that signal based task_work waking is invoked with the sighand
  wait queue head lock.

  The motivation for this work is to decouple signal notify based
  task_work, of which io_uring is a heavy user of, from sighand. The
  sighand lock becomes a huge contention point, particularly for
  threaded workloads where it's shared between threads. Even outside of
  threaded applications it's slower than it needs to be.

  Roman Gershman <romger@amazon.com> reported that his networked
  workload dropped from 1.6M QPS at 80% CPU to 1.0M QPS at 100% CPU
  after io_uring was changed to use TIF_NOTIFY_SIGNAL. The time was all
  spent hammering on the sighand lock, showing 57% of the CPU time there
  [1].

  There are further cleanups possible on top of this. One example is
  TIF_PATCH_PENDING, where a patch already exists to use
  TIF_NOTIFY_SIGNAL instead. Hopefully this will also lead to more
  consolidation, but the work stands on its own as well"

[1] https://github.com/axboe/liburing/issues/215

* tag 'tif-task_work.arch-2020-12-14' of git://git.kernel.dk/linux-block: (28 commits)
  io_uring: remove 'twa_signal_ok' deadlock work-around
  kernel: remove checking for TIF_NOTIFY_SIGNAL
  signal: kill JOBCTL_TASK_WORK
  io_uring: JOBCTL_TASK_WORK is no longer used by task_work
  task_work: remove legacy TWA_SIGNAL path
  sparc: add support for TIF_NOTIFY_SIGNAL
  riscv: add support for TIF_NOTIFY_SIGNAL
  nds32: add support for TIF_NOTIFY_SIGNAL
  ia64: add support for TIF_NOTIFY_SIGNAL
  h8300: add support for TIF_NOTIFY_SIGNAL
  c6x: add support for TIF_NOTIFY_SIGNAL
  alpha: add support for TIF_NOTIFY_SIGNAL
  xtensa: add support for TIF_NOTIFY_SIGNAL
  arm: add support for TIF_NOTIFY_SIGNAL
  microblaze: add support for TIF_NOTIFY_SIGNAL
  hexagon: add support for TIF_NOTIFY_SIGNAL
  csky: add support for TIF_NOTIFY_SIGNAL
  openrisc: add support for TIF_NOTIFY_SIGNAL
  sh: add support for TIF_NOTIFY_SIGNAL
  um: add support for TIF_NOTIFY_SIGNAL
  ...
2020-12-16 12:33:35 -08:00
Jens Axboe
24a31b81e3 riscv: add support for TIF_NOTIFY_SIGNAL
Wire up TIF_NOTIFY_SIGNAL handling for riscv.

Cc: linux-riscv@lists.infradead.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-12 09:17:38 -07:00
Souptick Joarder
3ae9c3cde5
riscv: Fixed kernel test robot warning
Kernel test robot throws below warning -

   arch/riscv/kernel/asm-offsets.c:14:6: warning: no previous prototype
for 'asm_offsets' [-Wmissing-prototypes]
      14 | void asm_offsets(void)
         |      ^~~~~~~~~~~

This patch should fixed it.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-12-10 17:47:23 -08:00
Kefeng Wang
772e1b7c42
riscv: kernel: Drop unused clean rule
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-12-10 17:42:34 -08:00
Nylon Chen
04091d6c05
riscv: provide memmove implementation
The memmove used by the kernel feature like KASAN.

Signed-off-by: Nick Hu <nickhu@andestech.com>
Signed-off-by: Nick Hu <nick650823@gmail.com>
Signed-off-by: Nylon Chen <nylon7@andestech.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-12-10 17:27:54 -08:00
Linus Torvalds
f91a3aa6bc Yet two more places which invoke tracing from RCU disabled regions in the
idle path. Similar to the entry path the low level idle functions have to
 be non-instrumentable.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl/DpAUTHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoXSLD/9klc0YimnEnROW6Q5Svb2IcyIutmXF
 bOIY1bYYoKILOBj3wyvDUhmdMuq5zh7H9yG11hO8MaVVWVQcLcOMLdHTYm9dcdmF
 xQk33+xqjuhRShB+nEmC9ayYtWogtH6W6uZ6WDtF9ZltMKU85n5ddGJ/Fvo+HoCb
 NbOdHGJdJ3/3ZCeHnxOnxM+5/GwjkBuccTV/tXmb3yXrfU9DBySyQ4/UchcpF43w
 LcEb0kiQbpZsBTByKJOQV8+RR654S0sILlvRwVXpmj94vrgGwhlVk1/9rz7tkOhF
 ksoo1mTVu75LMt22G/hXxE63787yRvFdHjapf0+kCOAuhl992NK+xlGDH8o9DXcu
 9y73D4bI0HnDFs20w6vs20iLvxECJiYHJqlgR5ZwFUToceaNgtiYr8kzuD7Zbae1
 KG2E7BuNSwHWMtf97fGn44GZknPEOaKdDn4Wv6/bvKHxLm77qe11RKF70Stcz2AI
 am13KmQzzsHGF5qNWwpElRUxSdxfJMR66RnOdTQULGrRedaZTFol/y2pnVzTSe3k
 SZnlpL5kE7y92UYDogPb5wWA7b+YkJN0OdSkRFy1FH26ZG8E4M7ZJ2tql5Sw7pGM
 lsTjXpAUphnK5rz7QcYE8KAZWj//fIAcElIrvdklVcBnS3IqjfksYW27B64133vx
 cT1B/lA1PHXj6Q==
 =raED
 -----END PGP SIGNATURE-----

Merge tag 'locking-urgent-2020-11-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking fixes from Thomas Gleixner:
 "Two more places which invoke tracing from RCU disabled regions in the
  idle path.

  Similar to the entry path the low level idle functions have to be
  non-instrumentable"

* tag 'locking-urgent-2020-11-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  intel_idle: Fix intel_idle() vs tracing
  sched/idle: Fix arch_cpu_idle() vs tracing
2020-11-29 11:19:26 -08:00
Atish Patra
b5b11a8ac4
RISC-V: Move dynamic relocation section under __init
Dynamic relocation section are only required during boot. Those sections
can be freed after init. Thus, it can be moved to __init section.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Tested-by: Greentime Hu <greentime.hu@sifive.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-11-25 16:05:29 -08:00
Atish Patra
19a0086902
RISC-V: Protect all kernel sections including init early
Currently, .init.text & .init.data are intermixed which makes it impossible
apply different permissions to them. .init.data shouldn't need exec
permissions while .init.text shouldn't have write permission. Moreover,
the strict permission are only enforced /init starts. This leaves the
kernel vulnerable from possible buggy built-in modules.

Keep .init.text & .data in separate sections so that different permissions
are applied to each section. Apply permissions to individual sections as
early as possible. This improves the kernel protection under
CONFIG_STRICT_KERNEL_RWX. We also need to restore the permissions for the
entire _init section after it is freed so that those pages can be used
for other purpose.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Tested-by: Greentime Hu <greentime.hu@sifive.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-11-25 16:05:28 -08:00
Atish Patra
b6566dc1ac
RISC-V: Align the .init.text section
In order to improve kernel text protection, we need separate .init.text/
.init.data/.text in separate sections. However, RISC-V linker relaxation
code is not aware of any alignment between sections. As a result, it may
relax any RISCV_CALL relocations between sections to JAL without realizing
that an inter section alignment may move the address farther. That may
lead to a relocation truncated fit error. However, linker relaxation code
is aware of the individual section alignments.

The detailed discussion on this issue can be found here.
https://github.com/riscv/riscv-gnu-toolchain/issues/738

Keep the .init.text section aligned so that linker relaxation will take
that as a hint while relaxing inter section calls.
Here are the code size changes for each section because of this change.

section         change in size (in bytes)
  .head.text      +4
  .text           +40
  .init.text      +6530
  .exit.text      +84

The only significant increase in size happened for .init.text because
all intra relocations also use 2MB alignment.

Suggested-by: Jim Wilson <jimw@sifive.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Tested-by: Greentime Hu <greentime.hu@sifive.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-11-25 16:05:27 -08:00
Atish Patra
62149f3564
RISC-V: Initialize SBI early
Currently, SBI is initialized towards the end of arch setup. This prevents
the set memory operations to be invoked earlier as it requires a full tlb
flush.

Initialize SBI as early as possible.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Tested-by: Greentime Hu <greentime.hu@sifive.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-11-25 16:05:17 -08:00
Kefeng Wang
5cb0080f1b
riscv: Enable ARCH_STACKWALK
Convert to ARCH_STACKWALK to reduce duplicated code in stack trace.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-11-25 16:03:59 -08:00
Anup Patel
6134b110f9
RISC-V: Add missing jump label initialization
The jump_label_init() should be called from setup_arch() very
early for proper functioning of jump label support.

Fixes: ebc00dde8a ("riscv: Add jump-label implementation")
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-11-25 09:44:25 -08:00
Nathan Chancellor
e553fdc810
riscv: Explicitly specify the build id style in vDSO Makefile again
Commit a968433723 ("kbuild: explicitly specify the build id style")
explicitly set the build ID style to SHA1. Commit c2c81bb2f6 ("RISC-V:
Fix the VDSO symbol generaton for binutils-2.35+") undid this change,
likely unintentionally.

Restore it so that the build ID style stays consistent across the tree
regardless of linker.

Fixes: c2c81bb2f6 ("RISC-V: Fix the VDSO symbol generaton for binutils-2.35+")
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Bill Wendling <morbo@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-11-25 09:44:14 -08:00
Peter Zijlstra
58c644ba51 sched/idle: Fix arch_cpu_idle() vs tracing
We call arch_cpu_idle() with RCU disabled, but then use
local_irq_{en,dis}able(), which invokes tracing, which relies on RCU.

Switch all arch_cpu_idle() implementations to use
raw_local_irq_{en,dis}able() and carefully manage the
lockdep,rcu,tracing state like we do in entry.

(XXX: we really should change arch_cpu_idle() to not return with
interrupts enabled)

Reported-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lkml.kernel.org/r/20201120114925.594122626@infradead.org
2020-11-24 16:47:35 +01:00
Kefeng Wang
9dd97064e2
riscv: Make stack walk callback consistent with generic code
In order to use generic arch_stack_walk() code, make stack walk
callback consistent with it.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-11-20 18:53:38 -08:00