Add fn and fn_arg members into struct kernel_clone_args and test for
them in copy_thread (instead of testing for PF_KTHREAD | PF_IO_WORKER).
This allows any task that wants to be a user space task that only runs
in kernel mode to use this functionality.
The code on x86 is an exception and still retains a PF_KTHREAD test
because x86 unlikely everything else handles kthreads slightly
differently than user space tasks that start with a function.
The functions that created tasks that start with a function
have been updated to set ".fn" and ".fn_arg" instead of
".stack" and ".stack_size". These functions are fork_idle(),
create_io_thread(), kernel_thread(), and user_mode_thread().
Link: https://lkml.kernel.org/r/20220506141512.516114-4-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
With io_uring we have started supporting tasks that are for most
purposes user space tasks that exclusively run code in kernel mode.
The kernel task that exec's init and tasks that exec user mode
helpers are also user mode tasks that just run kernel code
until they call kernel execve.
Pass kernel_clone_args into copy_thread so these oddball
tasks can be supported more cleanly and easily.
v2: Fix spelling of kenrel_clone_args on h8300
Link: https://lkml.kernel.org/r/20220506141512.516114-2-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
The functions get_online_cpus() and put_online_cpus() have been
deprecated during the CPU hotplug rework. They map directly to
cpus_read_lock() and cpus_read_unlock().
Replace deprecated CPU-hotplug functions with the official version.
The behavior remains unchanged.
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: linux-mips@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
All get_fs/set_fs calls in MIPS code are gone, so remove implementation
of it. With the clear separation of user/kernel space access we no
longer need the EVA special handling, so get rid of that, too.
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
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>
For those leaf functions, they are likely to have no stack operations.
Add is_jr_ra_ins() to determine whether jr ra has been touched before
the frame_size is found. Without this patch, the get frame_size operation
may be out of range and get the frame_size from the next nested function.
There is no POOL32A format in uapi/asm/inst.h, so some bits here use the
format of r_format instead.
e.g.
---------------------------------------------------------------------
| format | 31:26 | 25:21 | 20:16 | 15:6 | 5:0 |
-----------------+---------+-------+-------+------------+------------
| pool32a_format | pool32a | rt | rs | jalrc | pool32axf |
-----------------+---------+-------+-------+------------+------------
| r_format | opcode | rs | rt | rd:5, re:5 | func |
---------------------------------------------------------------------
Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
[1]: Commit b6c7a324df ("MIPS: Fix get_frame_info() handling of
microMIPS function size")
[2]: Commit 2b424cfc69 ("MIPS: Remove function size check in
get_frame_info()")
First patch added a constant to check the number of iterations against.
Second patch fixed the situation that info->func_size is zero.
However, func_size member became useless after the second commit. Without
ip_end, the get frame_size operation may be out of range although KALLSYMS
enabled. Thus, check func_size first. Then make ip_end be the sum of ip
and a constant (512) if func_size is equal to 0. Otherwise make ip_end be
the sum of ip and func_size.
Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
mm16_r5_format.rt is 5 bits, so directly judge the value if equal or not.
mm_jalr_op requires 7th to 16th bits. These 10 which bits generated by
shifting u_format.uimmediate by 6 may be affected by sign extension.
Thus, take out the 10 bits for comparison.
Without this patch, errors may occur, such as these bits are all ones.
Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Get rid of the __call_single_node union and cleanup the API a little
to avoid external code relying on the structure layout as much.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
arch/mips/kernel/process.c:696:15: error: no previous prototype for 'arch_align_stack' [-Werror=missing-prototypes]
Signed-off-by: Pujin Shi <shipujin.t@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Loongson-3 has 16-bytes load/store instructions: gslq and gssq. This
patch calculate ra properly when unwinding the stack, if ra is saved
by gssq and restored by gslq.
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Loongson-3's COP2 is Multi-Media coprocessor, it is disabled in kernel
mode by default. However, gslq/gssq (16-bytes load/store instructions)
overrides the instruction format of lwc2/swc2. If we wan't to use gslq/
gssq for optimization in kernel, we should enable COP2 usage in kernel.
Please pay attention that in this patch we only enable COP2 in kernel,
which means it will lose ST0_CU2 when a process go to user space (try
to use COP2 in user space will trigger an exception and then grab COP2,
which is similar to FPU). And as a result, we need to modify the context
switching code because the new scheduled process doesn't contain ST0_CU2
in its THERAD_STATUS probably.
For zboot, we disable gslq/gssq be generated by toolchain.
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Patch (b6c7a324df "MIPS: Fix get_frame_info() handling of
microMIPS function size.") introduces additional function size
check for microMIPS by only checking insn between ip and ip + func_size.
However, func_size in get_frame_info() is always 0 if KALLSYMS is not
enabled. This causes get_frame_info() to return immediately without
calculating correct frame_size, which in turn causes "Can't analyze
schedule() prologue" warning messages at boot time.
This patch removes func_size check, and let the frame_size check run
up to 128 insns for both MIPS and microMIPS.
Signed-off-by: Jun-Ru Chang <jrjang@realtek.com>
Signed-off-by: Tony Wu <tonywu@realtek.com>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Fixes: b6c7a324df ("MIPS: Fix get_frame_info() handling of microMIPS function size.")
Cc: <ralf@linux-mips.org>
Cc: <jhogan@kernel.org>
Cc: <macro@mips.com>
Cc: <yamada.masahiro@socionext.com>
Cc: <peterz@infradead.org>
Cc: <mingo@kernel.org>
Cc: <linux-mips@vger.kernel.org>
Cc: <linux-kernel@vger.kernel.org>
The fp_mode_switching field in struct mm_context_t was left unused by
commit 8c8d953c28 ("MIPS: Schedule on CPUs we need to lose FPU for a
mode switch") in v4.19, with nothing modifying its value & nothing
waiting on it having any particular value after that commit. Remove the
unused field & the one remaining reference to it.
Signed-off-by: Paul Burton <paul.burton@mips.com>
When using the legacy mmap layout, for example triggered using ulimit -s
unlimited, get_unmapped_area() fills memory from bottom to top starting
from a fairly low address near TASK_UNMAPPED_BASE.
This placement is suboptimal if the user application wishes to allocate
large amounts of heap memory using the brk syscall. With the VDSO being
located low in the user's virtual address space, the amount of space
available for access using brk is limited much more than it was prior to
the introduction of the VDSO.
For example:
# ulimit -s unlimited; cat /proc/self/maps
00400000-004ec000 r-xp 00000000 08:00 71436 /usr/bin/coreutils
004fc000-004fd000 rwxp 000ec000 08:00 71436 /usr/bin/coreutils
004fd000-0050f000 rwxp 00000000 00:00 0
00cc3000-00ce4000 rwxp 00000000 00:00 0 [heap]
2ab96000-2ab98000 r--p 00000000 00:00 0 [vvar]
2ab98000-2ab99000 r-xp 00000000 00:00 0 [vdso]
2ab99000-2ab9d000 rwxp 00000000 00:00 0
...
Resolve this by adjusting STACK_TOP to reserve space for the VDSO &
providing an address hint to get_unmapped_area() causing it to use this
space even when using the legacy mmap layout.
We reserve enough space for the VDSO, plus 1MB or 256MB for 32 bit & 64
bit systems respectively within which we randomize the VDSO base
address. Previously this randomization was taken care of by the mmap
base address randomization performed by arch_mmap_rnd(). The 1MB & 256MB
sizes are somewhat arbitrary but chosen such that we have some
randomization without taking up too much of the user's virtual address
space, which is often in short supply for 32 bit systems.
With this the VDSO is always mapped at a high address, leaving lots of
space for statically linked programs to make use of brk:
# ulimit -s unlimited; cat /proc/self/maps
00400000-004ec000 r-xp 00000000 08:00 71436 /usr/bin/coreutils
004fc000-004fd000 rwxp 000ec000 08:00 71436 /usr/bin/coreutils
004fd000-0050f000 rwxp 00000000 00:00 0
00c28000-00c49000 rwxp 00000000 00:00 0 [heap]
...
7f67c000-7f69d000 rwxp 00000000 00:00 0 [stack]
7f7fc000-7f7fd000 rwxp 00000000 00:00 0
7fcf1000-7fcf3000 r--p 00000000 00:00 0 [vvar]
7fcf3000-7fcf4000 r-xp 00000000 00:00 0 [vdso]
Signed-off-by: Paul Burton <paul.burton@mips.com>
Reported-by: Huacai Chen <chenhc@lemote.com>
Fixes: ebb5e78cc6 ("MIPS: Initial implementation of a VDSO")
Cc: Huacai Chen <chenhc@lemote.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org # v4.4+
Pull MIPS updates from Paul Burton:
"Here are the main MIPS changes for 4.19.
An overview of the general architecture changes:
- Massive DMA ops refactoring from Christoph Hellwig (huzzah for
deleting crufty code!).
- We introduce NT_MIPS_DSP & NT_MIPS_FP_MODE ELF notes &
corresponding regsets to expose DSP ASE & floating point mode state
respectively, both for live debugging & core dumps.
- We better optimize our code by hard-coding cpu_has_* macros at
compile time where their values are known due to the ISA revision
that the kernel build is targeting.
- The EJTAG exception handler now better handles SMP systems, where
it was previously possible for CPUs to clobber a register value
saved by another CPU.
- Our implementation of memset() gained a couple of fixes for MIPSr6
systems to return correct values in some cases where stores fault.
- We now implement ioremap_wc() using the uncached-accelerated cache
coherency attribute where supported, which is detected during boot,
and fall back to plain uncached access where necessary. The
MIPS-specific (and unused in tree) ioremap_uncached_accelerated() &
ioremap_cacheable_cow() are removed.
- The prctl(PR_SET_FP_MODE, ...) syscall is better supported for SMP
systems by reworking the way we ensure remote CPUs that may be
running threads within the affected process switch mode.
- Systems using the MIPS Coherence Manager will now set the
MIPS_IC_SNOOPS_REMOTE flag to avoid some unnecessary cache
maintenance overhead when flushing the icache.
- A few fixes were made for building with clang/LLVM, which now
sucessfully builds kernels for many of our platforms.
- Miscellaneous cleanups all over.
And some platform-specific changes:
- ar7 gained stubs for a few clock API functions to fix build
failures for some drivers.
- ath79 gained support for a few new SoCs, a few fixes & better
gpio-keys support.
- Ci20 now exposes its SPI bus using the spi-gpio driver.
- The generic platform can now auto-detect a suitable value for
PHYS_OFFSET based upon the memory map described by the device tree,
allowing us to avoid wasting memory on page book-keeping for
systems where RAM starts at a non-zero physical address.
- Ingenic systems using the jz4740 platform code now link their
vmlinuz higher to allow for kernels of a realistic size.
- Loongson32 now builds the kernel targeting MIPSr1 rather than
MIPSr2 to avoid CPU errata.
- Loongson64 gains a couple of fixes, a workaround for a write
buffering issue & support for the Loongson 3A R3.1 CPU.
- Malta now uses the piix4-poweroff driver to handle powering down.
- Microsemi Ocelot gained support for its SPI bus & NOR flash, its
second MDIO bus and can now be supported by a FIT/.itb image.
- Octeon saw a bunch of header cleanups which remove a lot of
duplicate or unused code"
* tag 'mips_4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (123 commits)
MIPS: Remove remnants of UASM_ISA
MIPS: netlogic: xlr: Remove erroneous check in nlm_fmn_send()
MIPS: VDSO: Force link endianness
MIPS: Always specify -EB or -EL when using clang
MIPS: Use dins to simplify __write_64bit_c0_split()
MIPS: Use read-write output operand in __write_64bit_c0_split()
MIPS: Avoid using array as parameter to write_c0_kpgd()
MIPS: vdso: Allow clang's --target flag in VDSO cflags
MIPS: genvdso: Remove GOT checks
MIPS: Remove obsolete MIPS checks for DST node "chosen@0"
MIPS: generic: Remove input symbols from defconfig
MIPS: Delete unused code in linux32.c
MIPS: Remove unused sys_32_mmap2
MIPS: Remove nabi_no_regargs
mips: dts: mscc: enable spi and NOR flash support on ocelot PCB123
mips: dts: mscc: Add spi on Ocelot
MIPS: Loongson: Merge load addresses
MIPS: Loongson: Set Loongson32 to MIPS32R1
MIPS: mscc: ocelot: add interrupt controller properties to GPIO controller
MIPS: generic: Select MIPS_AUTO_PFN_OFFSET
...
