Commit Graph

215 Commits

Author SHA1 Message Date
Al Viro 51bb38cb78 csky: Fixup raw_copy_from_user()
If raw_copy_from_user(to, from, N) returns K, callers expect
the first N - K bytes starting at to to have been replaced with
the contents of corresponding area starting at from and the last
K bytes of destination *left* *unmodified*.

What arch/sky/lib/usercopy.c is doing is broken - it can lead to e.g.
data corruption on write(2).

raw_copy_to_user() is inaccurate about return value, which is a bug,
but consequences are less drastic than for raw_copy_from_user().
And just what are those access_ok() doing in there?  I mean, look into
linux/uaccess.h; that's where we do that check (as well as zero tail
on failure in the callers that need zeroing).

AFAICS, all of that shouldn't be hard to fix; something like a patch
below might make a useful starting point.

I would suggest moving these macros into usercopy.c (they are never
used anywhere else) and possibly expanding them there; if you leave
them alive, please at least rename __copy_user_zeroing(). Again,
it must not zero anything on failed read.

Said that, I'm not sure we won't be better off simply turning
usercopy.c into usercopy.S - all that is left there is a couple of
functions, each consisting only of inline asm.

Guo Ren reply:

Yes, raw_copy_from_user is wrong, it's no need zeroing code.

unsigned long _copy_from_user(void *to, const void __user *from,
unsigned long n)
{
        unsigned long res = n;
        might_fault();
        if (likely(access_ok(from, n))) {
                kasan_check_write(to, n);
                res = raw_copy_from_user(to, from, n);
        }
        if (unlikely(res))
                memset(to + (n - res), 0, res);
        return res;
}
EXPORT_SYMBOL(_copy_from_user);

You are right and access_ok() should be removed.

but, how about:
do {
...
        "2:     stw     %3, (%1, 0)     \n"             \
+       "       subi    %0, 4          \n"               \
        "9:     stw     %4, (%1, 4)     \n"             \
+       "       subi    %0, 4          \n"               \
        "10:    stw     %5, (%1, 8)     \n"             \
+       "       subi    %0, 4          \n"               \
        "11:    stw     %6, (%1, 12)    \n"             \
+       "       subi    %0, 4          \n"               \
        "       addi    %2, 16          \n"             \
        "       addi    %1, 16          \n"             \

Don't expand __ex_table

AI Viro reply:

Hey, I've no idea about the instruction scheduling on csky -
if that doesn't slow the things down, all the better.  It's just
that copy_to_user() and friends are on fairly hot codepaths,
and in quite a few situations they will dominate the speed of
e.g. read(2).  So I tried to keep the fast path unchanged.
Up to the architecture maintainers, obviously.  Which would be
you...

As for the fixups size increase (__ex_table size is unchanged)...
You have each of those macros expanded exactly once.
So the size is not a serious argument, IMO - useless complexity
would be, if it is, in fact, useless; the size... not really,
especially since those extra subi will at least offset it.

Again, up to you - asm optimizations of (essentially)
memcpy()-style loops are tricky and can depend upon the
fairly subtle details of architecture.  So even on something
I know reasonably well I would resort to direct experiments
if I can't pass the buck to architecture maintainers.

It *is* worth optimizing - this is where read() from a file
that is already in page cache spends most of the time, etc.

Guo Ren reply:

Thx, after fixup some typo “sub %0, 4”, apply the patch.

TODO:
 - user copy/from codes are still need optimizing.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-05-15 00:16:30 +08:00
Guo Ren 67002814cf csky: Fixup gdbmacros.txt with name sp in thread_struct
The gdbmacros.txt use sp in thread_struct, but csky use ksp. This
cause bttnobp fail to excute.

TODO:
 - Still couldn't display the contents of stack.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-05-15 00:16:18 +08:00
Guo Ren 9e2ca15322 csky: Fixup remove unnecessary save/restore PSR code
All processes' PSR could success from SETUP_MMU, so need set it
in INIT_THREAD again.

And use a3 instead of r7 in __switch_to for code convention.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-05-13 17:55:06 +08:00
Liu Yibin 6633a5aa8e csky: Fixup remove duplicate irq_disable
Interrupt has been disabled in __schedule() with local_irq_disable()
and enabled in finish_task_switch->finish_lock_switch() with
local_irq_enabled(), So needn't to disable irq here.

Signed-off-by: Liu Yibin <jiulong@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-05-13 17:55:06 +08:00
Guo Ren 18c07d23da csky: Fixup calltrace panic
The implementation of show_stack will panic with wrong fp:

addr    = *fp++;

because the fp isn't checked properly.

The current implementations of show_stack, wchan and stack_trace
haven't been designed properly, so just deprecate them.

This patch is a reference to riscv's way, all codes are modified from
arm's. The patch is passed with:

 - cat /proc/<pid>/stack
 - cat /proc/<pid>/wchan
 - echo c > /proc/sysrq-trigger

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-05-13 17:55:06 +08:00
Mao Han 229a0ddee1 csky: Fixup perf callchain unwind
[ 5221.974084] Unable to handle kernel paging request at virtual address 0xfffff000, pc: 0x8002c18e
 [ 5221.985929] Oops: 00000000
 [ 5221.989488]
 [ 5221.989488] CURRENT PROCESS:
 [ 5221.989488]
 [ 5221.992877] COMM=callchain_test PID=11962
 [ 5221.995213] TEXT=00008000-000087e0 DATA=00009f1c-0000a018 BSS=0000a018-0000b000
 [ 5221.999037] USER-STACK=7fc18e20  KERNEL-STACK=be204680
 [ 5221.999037]
 [ 5222.003292] PC: 0x8002c18e (perf_callchain_kernel+0x3e/0xd4)
 [ 5222.007957] LR: 0x8002c198 (perf_callchain_kernel+0x48/0xd4)
 [ 5222.074873] Call Trace:
 [ 5222.074873] [<800a248e>] get_perf_callchain+0x20a/0x29c
 [ 5222.074873] [<8009d964>] perf_callchain+0x64/0x80
 [ 5222.074873] [<8009dc1c>] perf_prepare_sample+0x29c/0x4b8
 [ 5222.074873] [<8009de6e>] perf_event_output_forward+0x36/0x98
 [ 5222.074873] [<800497e0>] search_exception_tables+0x20/0x44
 [ 5222.074873] [<8002cbb6>] do_page_fault+0x92/0x378
 [ 5222.074873] [<80098608>] __perf_event_overflow+0x54/0xdc
 [ 5222.074873] [<80098778>] perf_swevent_hrtimer+0xe8/0x164
 [ 5222.074873] [<8002ddd0>] update_mmu_cache+0x0/0xd8
 [ 5222.074873] [<8002c014>] user_backtrace+0x58/0xc4
 [ 5222.074873] [<8002c0b4>] perf_callchain_user+0x34/0xd0
 [ 5222.074873] [<800a2442>] get_perf_callchain+0x1be/0x29c
 [ 5222.074873] [<8009d964>] perf_callchain+0x64/0x80
 [ 5222.074873] [<8009d834>] perf_output_sample+0x78c/0x858
 [ 5222.074873] [<8009dc1c>] perf_prepare_sample+0x29c/0x4b8
 [ 5222.074873] [<8009de94>] perf_event_output_forward+0x5c/0x98
 [ 5222.097846]
 [ 5222.097846] [<800a0300>] perf_event_exit_task+0x58/0x43c
 [ 5222.097846] [<8006c874>] hrtimer_interrupt+0x104/0x2ec
 [ 5222.097846] [<800a0300>] perf_event_exit_task+0x58/0x43c
 [ 5222.097846] [<80437bb6>] dw_apb_clockevent_irq+0x2a/0x4c
 [ 5222.097846] [<8006c770>] hrtimer_interrupt+0x0/0x2ec
 [ 5222.097846] [<8005f2e4>] __handle_irq_event_percpu+0xac/0x19c
 [ 5222.097846] [<80437bb6>] dw_apb_clockevent_irq+0x2a/0x4c
 [ 5222.097846] [<8005f408>] handle_irq_event_percpu+0x34/0x88
 [ 5222.097846] [<8005f480>] handle_irq_event+0x24/0x64
 [ 5222.097846] [<8006218c>] handle_level_irq+0x68/0xdc
 [ 5222.097846] [<8005ec76>] __handle_domain_irq+0x56/0xa8
 [ 5222.097846] [<80450e90>] ck_irq_handler+0xac/0xe4
 [ 5222.097846] [<80029012>] csky_do_IRQ+0x12/0x24
 [ 5222.097846] [<8002a3a0>] csky_irq+0x70/0x80
 [ 5222.097846] [<800ca612>] alloc_set_pte+0xd2/0x238
 [ 5222.097846] [<8002ddd0>] update_mmu_cache+0x0/0xd8
 [ 5222.097846] [<800a0340>] perf_event_exit_task+0x98/0x43c

The original fp check doesn't base on the real kernal stack region.
Invalid fp address may cause kernel panic.

Signed-off-by: Mao Han <han_mao@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-05-13 17:55:05 +08:00
Liu Yibin 165f2d2858 csky: Fixup msa highest 3 bits mask
Just as comment mentioned, the msa format:

 cr<30/31, 15> MSA register format:
 31 - 29 | 28 - 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0
   BA     Reserved  SH  WA  B   SO SEC  C   D   V

So we should shift 29 bits not 28 bits for mask

Signed-off-by: Liu Yibin <jiulong@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-05-13 17:55:05 +08:00
Guo Ren c2e59d1f4d csky: Fixup perf probe -x hungup
case:
 # perf probe -x /lib/libc-2.28.9000.so memcpy
 # perf record -e probe_libc:memcpy -aR sleep 1

System hangup and cpu get in trap_c loop, because our hardware
singlestep state could still get interrupt signal. When we get in
uprobe_xol singlestep slot, we should disable irq in pt_regs->psr.

And is_swbp_insn() need a csky arch implementation with a low 16bit
mask.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-05-13 17:55:05 +08:00
Guo Ren bd11aabd35 csky: Fixup compile error for abiv1 entry.S
This bug is from uprobe signal definition in thread_info.h. The
instruction (andi) of abiv1 immediate is smaller than abiv2, then
it will cause:

  AS      arch/csky/kernel/entry.o
 arch/csky/kernel/entry.S: Assembler messages:
 arch/csky/kernel/entry.S:224: Error: Operand 2 immediate is overflow.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-05-13 17:55:05 +08:00
Guo Ren a13d5887ff csky/ftrace: Fixup error when disable CONFIG_DYNAMIC_FTRACE
When CONFIG_DYNAMIC_FTRACE is enabled, static ftrace will fail to
boot up and compile. It's a carelessness when developing "dynamic
ftrace" and "ftrace with regs".

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-05-13 17:55:05 +08:00
Anshuman Khandual 78e7c5af08 mm/special: create generic fallbacks for pte_special() and pte_mkspecial()
Currently there are many platforms that dont enable ARCH_HAS_PTE_SPECIAL
but required to define quite similar fallback stubs for special page
table entry helpers such as pte_special() and pte_mkspecial(), as they
get build in generic MM without a config check.  This creates two
generic fallback stub definitions for these helpers, eliminating much
code duplication.

mips platform has a special case where pte_special() and pte_mkspecial()
visibility is wider than what ARCH_HAS_PTE_SPECIAL enablement requires.
This restricts those symbol visibility in order to avoid redefinitions
which is now exposed through this new generic stubs and subsequent build
failure.  arm platform set_pte_at() definition needs to be moved into a
C file just to prevent a build failure.

[anshuman.khandual@arm.com: use defined(CONFIG_ARCH_HAS_PTE_SPECIAL) in mips per Thomas]
  Link: http://lkml.kernel.org/r/1583851924-21603-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Guo Ren <guoren@kernel.org>			[csky]
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>	[m68k]
Acked-by: Stafford Horne <shorne@gmail.com>		[openrisc]
Acked-by: Helge Deller <deller@gmx.de>			[parisc]
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Sam Creasey <sammy@sammy.net>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Link: http://lkml.kernel.org/r/1583802551-15406-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10 15:36:21 -07:00
Anshuman Khandual c62da0c35d mm/vma: define a default value for VM_DATA_DEFAULT_FLAGS
There are many platforms with exact same value for VM_DATA_DEFAULT_FLAGS
This creates a default value for VM_DATA_DEFAULT_FLAGS in line with the
existing VM_STACK_DEFAULT_FLAGS.  While here, also define some more
macros with standard VMA access flag combinations that are used
frequently across many platforms.  Apart from simplification, this
reduces code duplication as well.

Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Rich Felker <dalias@libc.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Chris Zankel <chris@zankel.net>
Link: http://lkml.kernel.org/r/1583391014-8170-2-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10 15:36:21 -07:00
Anshuman Khandual 5093c5872b mm/vma: append unlikely() while testing VMA access permissions
It is unlikely that an inaccessible VMA without required permission flags
will get a page fault.  Hence lets just append unlikely() directive to
such checks in order to improve performance while also standardizing it
across various platforms.

Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Link: http://lkml.kernel.org/r/1582525304-32113-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07 10:43:38 -07:00
Anshuman Khandual 3122e80efc mm/vma: make vma_is_accessible() available for general use
Lets move vma_is_accessible() helper to include/linux/mm.h which makes it
available for general use.  While here, this replaces all remaining open
encodings for VMA access check with vma_is_accessible().

Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Guo Ren <guoren@kernel.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Guo Ren <guoren@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Nick Piggin <npiggin@gmail.com>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/1582520593-30704-3-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07 10:43:37 -07:00
Linus Torvalds f183d269cc csky updates for 5.7-rc1
- Add kproobes/uprobes support
  - Add lockdep, rseq, gcov support
  - Fixup init_fpu
  - Fixup ftrace_modify deadlock
  - Fixup speculative execution on IO area
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Merge tag 'csky-for-linus-5.7-rc1' of git://github.com/c-sky/csky-linux

Pull csky updates from Guo Ren:

 - Add kproobes/uprobes support

 - Add lockdep, rseq, gcov support

 - Fixup init_fpu

 - Fixup ftrace_modify deadlock

 - Fixup speculative execution on IO area

* tag 'csky-for-linus-5.7-rc1' of git://github.com/c-sky/csky-linux:
  csky: Fixup cpu speculative execution to IO area
  csky: Add uprobes support
  csky: Add kprobes supported
  csky: Enable LOCKDEP_SUPPORT
  csky: Enable the gcov function
  csky: Fixup get wrong psr value from phyical reg
  csky/ftrace: Fixup ftrace_modify_code deadlock without CPU_HAS_ICACHE_INS
  csky: Implement ftrace with regs
  csky: Add support for restartable sequence
  csky: Implement ptrace regs and stack API
  csky: Fixup init_fpu compile warning with __init
2020-04-06 09:55:50 -07:00
Guo Ren aefd9461d3 csky: Fixup cpu speculative execution to IO area
For the memory size ( > 512MB, < 1GB), the MSA setting is:

 - SSEG0: PHY_START        , PHY_START + 512MB
 - SSEG1: PHY_START + 512MB, PHY_START + 1GB

But the real memory is no more than 1GB, there is a gap between the
end size of memory and border of 1GB. CPU could speculatively
execute to that gap and if the gap of the bus couldn't respond to
the CPU request, then the crash will happen.

Now make the setting with:

 - SSEG0: PHY_START        , PHY_START + 512MB (no change)
 - SSEG1: Disabled (We use highmem to use the memory of 512MB~1GB)

We also deprecated zhole_szie[] settings, it's only used by arm
style CPUs. All memory gap should use Reserved setting of dts in
csky system.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-04-03 12:40:07 +08:00
Guo Ren 8f6bb793b2 csky: Add uprobes support
This patch adds support for uprobes on csky architecture.

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

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-04-03 11:37:51 +08:00
Guo Ren 33e53ae1ce csky: Add kprobes supported
This patch enable kprobes, kretprobes, ftrace interface. It utilized
software breakpoint and single step debug exceptions, instructions
simulation on csky.

We use USR_BKPT replace origin instruction, and the kprobe handler
prepares an excutable memory slot for out-of-line execution with a
copy of the original instruction being probed. Most of instructions
could be executed by single-step, but some instructions need origin
pc value to execute and we need software simulate these instructions.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-04-03 11:14:17 +08:00
Masahiro Yamada 630f289b71 asm-generic: make more kernel-space headers mandatory
Change a header to mandatory-y if both of the following are met:

[1] At least one architecture (except um) specifies it as generic-y in
    arch/*/include/asm/Kbuild

[2] Every architecture (except um) either has its own implementation
    (arch/*/include/asm/*.h) or specifies it as generic-y in
    arch/*/include/asm/Kbuild

This commit was generated by the following shell script.

----------------------------------->8-----------------------------------

arches=$(cd arch; ls -1 | sed -e '/Kconfig/d' -e '/um/d')

tmpfile=$(mktemp)

grep "^mandatory-y +=" include/asm-generic/Kbuild > $tmpfile

find arch -path 'arch/*/include/asm/Kbuild' |
	xargs sed -n 's/^generic-y += \(.*\)/\1/p' | sort -u |
while read header
do
	mandatory=yes

	for arch in $arches
	do
		if ! grep -q "generic-y += $header" arch/$arch/include/asm/Kbuild &&
			! [ -f arch/$arch/include/asm/$header ]; then
			mandatory=no
			break
		fi
	done

	if [ "$mandatory" = yes ]; then
		echo "mandatory-y += $header" >> $tmpfile

		for arch in $arches
		do
			sed -i "/generic-y += $header/d" arch/$arch/include/asm/Kbuild
		done
	fi

done

sed -i '/^mandatory-y +=/d' include/asm-generic/Kbuild

LANG=C sort $tmpfile >> include/asm-generic/Kbuild

----------------------------------->8-----------------------------------

One obvious benefit is the diff stat:

 25 files changed, 52 insertions(+), 557 deletions(-)

It is tedious to list generic-y for each arch that needs it.

So, mandatory-y works like a fallback default (by just wrapping
asm-generic one) when arch does not have a specific header
implementation.

See the following commits:

def3f7cefe
a1b39bae16

It is tedious to convert headers one by one, so I processed by a shell
script.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Link: http://lkml.kernel.org/r/20200210175452.5030-1-masahiroy@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:25 -07:00
Guo Ren 000591f1ca csky: Enable LOCKDEP_SUPPORT
Lockdep is needed by proving the spinlocks and rwlocks. Currently,
we only put trace_hardirqs_on/off with csky_irq and
ret_from_exception.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-04-02 19:39:42 +08:00
Ma Jun de86367871 csky: Enable the gcov function
Support the gcov function in csky architecture.

Signed-off-by: Ma Jun <majun258@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
2020-04-01 00:06:52 +08:00
Guo Ren 9c0e343d76 csky: Fixup get wrong psr value from phyical reg
We should get psr value from regs->psr in stack, not directly get
it from phyiscal register then save the vector number in
tsk->trap_no.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-04-01 00:06:40 +08:00
Guo Ren dd7c983e78 csky/ftrace: Fixup ftrace_modify_code deadlock without CPU_HAS_ICACHE_INS
If ICACHE_INS is not supported, we use IPI to sync icache on each
core. But ftrace_modify_code is called from stop_machine from default
implementation of arch_ftrace_update_code and stop_machine callback
is irq_disabled. When you call ipi with irq_disabled, a deadlock will
happen.

We couldn't use icache_flush with irq_disabled, but startup make_nop
is specific case and it needn't ipi other cores.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-03-31 22:15:42 +08:00
Sebastian Andrzej Siewior c5eedbae2f csky: Remove mm.h from asm/uaccess.h
The defconfig compiles without linux/mm.h. With mm.h included the
include chain leands to:
|   CC      kernel/locking/percpu-rwsem.o
| In file included from include/linux/huge_mm.h:8,
|                  from include/linux/mm.h:567,
|                  from arch/csky/include/asm/uaccess.h:,
|                  from include/linux/uaccess.h:11,
|                  from include/linux/sched/task.h:11,
|                  from include/linux/sched/signal.h:9,
|                  from include/linux/rcuwait.h:6,
|                  from include/linux/percpu-rwsem.h:8,
|                  from kernel/locking/percpu-rwsem.c:6:
| include/linux/fs.h:1422:29: error: array type has incomplete element type 'struct percpu_rw_semaphore'
|  1422 |  struct percpu_rw_semaphore rw_sem[SB_FREEZE_LEVELS];

once rcuwait.h includes linux/sched/signal.h.

Remove the linux/mm.h include.

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200321113241.434999165@linutronix.de
2020-03-21 16:00:21 +01:00
Guo Ren 89a3927a77 csky: Implement ftrace with regs
This patch implements FTRACE_WITH_REGS for csky, which allows a traced
function's arguments (and some other registers) to be captured into a
struct pt_regs, allowing these to be inspected and/or modified.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-03-08 20:55:14 +08:00
Guo Ren 9866d141a0 csky: Add support for restartable sequence
Copied and adapted from vincent's patch, but modified for csky.

ref:
https://lore.kernel.org/linux-riscv/1572919114-3886-3-git-send-email-vincent.chen@sifive.com/raw

Add calls to rseq_signal_deliver(), rseq_handle_notify_resume() and
rseq_syscall() to introduce RSEQ support.

1. Call the rseq_handle_notify_resume() function on return to userspace
   if TIF_NOTIFY_RESUME thread flag is set.

2. Call the rseq_signal_deliver() function to fixup on the pre-signal
   frame when a signal is delivered on top of a restartable sequence
   critical section.

3. Check that system calls are not invoked from within rseq critical
   sections by invoking rseq_signal() from ret_from_syscall(). With
   CONFIG_DEBUG_RSEQ, such behavior results in termination of the
   process with SIGSEGV.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-03-08 20:55:14 +08:00
Guo Ren bfe47f358a csky: Implement ptrace regs and stack API
Needed for kprobes support. Copied and adapted from Patrick's patch,
but it has been modified for csky's pt_regs.

ref:
https://lore.kernel.org/linux-riscv/1572919114-3886-2-git-send-email-vincent.chen@sifive.com/raw

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Patrick Staehlin <me@packi.ch>
2020-03-08 20:55:14 +08:00
Guo Ren 12879bda3c csky: Fixup init_fpu compile warning with __init
WARNING: vmlinux.o(.text+0x2366): Section mismatch in reference from the
function csky_start_secondary() to the function .init.text:init_fpu()

The function csky_start_secondary() references
the function __init init_fpu().
This is often because csky_start_secondary lacks a __init
annotation or the annotation of init_fpu is wrong.

Reported-by: Lu Chongzhi <chongzhi.lcz@alibaba-inc.com>
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-03-08 20:55:14 +08:00
Geert Uytterhoeven 99db590b08 csky: Replace <linux/clk-provider.h> by <linux/of_clk.h>
The C-Sky platform code is not a clock provider, and just needs to call
of_clk_init().

Hence it can include <linux/of_clk.h> instead of <linux/clk-provider.h>.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-02-23 12:48:55 +08:00
Guo Ren 0b9f386c4b csky: Implement copy_thread_tls
This is required for clone3 which passes the TLS value through a
struct rather than a register.

Cc: Amanieu d'Antras <amanieu@gmail.com>
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-02-21 15:43:25 +08:00
MaJun 5b49c82dad csky: Add PCI support
Add the pci related code for csky arch to support basic pci virtual
function, such as qemu virt-pci-9pfs.

Signed-off-by: MaJun <majun258@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-02-21 15:43:25 +08:00
Ma Jun dc2efc0028 csky: Minimize defconfig to support buildroot config.fragment
Some bsp (eg: buildroot) has defconfig.fragment design to add more
configs into the defconfig in linux source code tree. For example,
we could put different cpu configs into different defconfig.fragments,
but they all use the same defconfig in Linux.

Signed-off-by: Ma Jun <majun258@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-02-21 15:43:25 +08:00
Guo Ren d46869aaab csky: Add setup_initrd check code
We should give some necessary check for initrd just like other
architectures and it seems that setup_initrd() could be a common
code for all architectures.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-02-21 15:43:25 +08:00
Krzysztof Kozlowski 4ec575b785 csky: Cleanup old Kconfig options
CONFIG_CLKSRC_OF is gone since commit bb0eb050a5
("clocksource/drivers: Rename CLKSRC_OF to TIMER_OF").  The platform
already selects TIMER_OF.

CONFIG_HAVE_DMA_API_DEBUG is gone since commit 6e88628d03 ("dma-debug:
remove CONFIG_HAVE_DMA_API_DEBUG").

CONFIG_DEFAULT_DEADLINE is gone since commit f382fb0bce ("block:
remove legacy IO schedulers").

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-02-21 15:43:25 +08:00
Randy Dunlap bebd26ab62 arch/csky: fix some Kconfig typos
Fix wording in help text for the CPU_HAS_LDSTEX symbol.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Guo Ren <guoren@kernel.org>
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-02-21 15:43:25 +08:00
Guo Ren 2305f60b76 csky: Fixup compile warning for three unimplemented syscalls
Implement fstat64, fstatat64, clone3 syscalls to fixup
checksyscalls.sh compile warnings.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-02-21 15:43:25 +08:00
Guo Ren 9025fd48a8 csky: Remove unused cache implementation
Only for coding convention, these codes are unnecessary for abiv2.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-02-21 15:43:25 +08:00
Guo Ren 359ae00d12 csky: Fixup ftrace modify panic
During ftrace init, linux will replace all function prologues
(call_mcout) with nops, but it need flush_dcache and
invalidate_icache to make it work. So flush_cache functions
couldn't be nested called by ftrace framework.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-02-21 15:43:24 +08:00
Guo Ren 997153b9a7 csky: Add flush_icache_mm to defer flush icache all
Some CPUs don't support icache.va instruction to maintain the whole
smp cores' icache. Using icache.all + IPI casue a lot on performace
and using defer mechanism could reduce the number of calling icache
_flush_all functions.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-02-21 15:43:24 +08:00
Guo Ren cc1f6563a9 csky: Optimize abiv2 copy_to_user_page with VM_EXEC
Only when vma is for VM_EXEC, we need sync dcache & icache. eg:
 - gdb ptrace modify user space instruction code area.

Add VM_EXEC condition to reduce unnecessary cache flush.

The abiv1 cpus' cache are all VIPT, so we still need to deal with
dcache aliasing problem. But there is optimized way to use cache
color, just like what's done in arch/csky/abiv1/inc/abi/page.h.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-02-21 15:43:24 +08:00
Guo Ren d936a7e708 csky: Enable defer flush_dcache_page for abiv2 cpus (807/810/860)
Instead of flushing cache per update_mmu_cache() called, we use
flush_dcache_page to reduce the frequency of flashing the cache.

As abiv2 cpus are all PIPT for icache & dcache, we needn't handle
dcache aliasing problem. But their icache can't snoop dcache, so
we still need sync_icache_dcache in update_mmu_cache().

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-02-21 15:43:24 +08:00
Guo Ren a117673413 csky: Remove unnecessary flush_icache_* implementation
The abiv2 CPUs are all PIPT cache, so there is no need to implement
flush_icache_page function.

The function flush_icache_user_range hasn't been used, so just
remove it.

The function flush_cache_range is not necessary for PIPT cache when
tlb mapping changed.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-02-21 15:43:24 +08:00
Guo Ren 761b4f694c csky: Support icache flush without specific instructions
Some CPUs don't support icache specific instructions to flush icache
lines in broadcast way. We use cpu control registers to flush local
icache and use IPI to notify other cores.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-02-21 15:43:24 +08:00
Guo Ren a736fa1ed7 csky/Kconfig: Add Kconfig.platforms to support some drivers
Such as snps,dw-apb-ictl

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-02-21 15:43:24 +08:00
Guo Ren c9492737b2 csky/smp: Fixup boot failed when CONFIG_SMP
If we use a non-ipi-support interrupt controller, it will cause panic here.
We should let cpu up and work with CONFIG_SMP, when we use a non-ipi intc.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-02-21 15:43:24 +08:00
Guo Ren f8e17c17b8 csky: Set regs->usp to kernel sp, when the exception is from kernel
In the past, we didn't care about kernel sp when saving pt_reg. But in some
cases, we still need pt_reg->usp to represent the kernel stack before enter
exception.

For cmpxhg in atomic.S, we need save and restore usp for above.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-02-21 15:43:24 +08:00
Guo Ren 7f4a567332 csky/mm: Fixup export invalid_pte_table symbol
There is no present bit in csky pmd hardware, so we need to prepare invalid_pte_table
for empty pmd entry and the functions (pmd_none & pmd_present) in pgtable.h need
invalid_pte_talbe to get result. If a module use these functions, we need export the
symbol for it.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Cc: Mo Qihui <qihui.mo@verisilicon.com>
Cc: Zhange Jian <zhang_jian5@dahuatech.com>
2020-02-21 15:43:24 +08:00
Guo Ren f136008f31 csky: Separate fixaddr_init from highmem
After fixaddr_init is separated from highmem, we could use tcm
without highmem selected. (610 (abiv1) don't support highmem,
but it could use tcm now.)

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-02-21 15:43:24 +08:00
Guo Ren f525bb2c9e csky: Tightly-Coupled Memory or Sram support
The implementation are not only used by TCM but also used by sram on
SOC bus. It follow existed linux tcm software interface, so that old
tcm application codes could be re-used directly.

Software interface list in asm/tcm.h:
 - Variables/Const: 	__tcmdata, __tcmconst
 - Functions:		__tcmfunc, __tcmlocalfunc
 - Malloc/Free:		tcm_alloc, tcm_free

In linux menuconfig:
 - Choose a TCM contain instrctions + data or separated in ITCM/DTCM.
 - Determine TCM_BASE (DTCM_BASE) in phyiscal address.
 - Determine size of TCM or ITCM(DTCM) in page counts.

Here is hello tcm example from Documentation/arm/tcm.rst which could
be directly used:

/* Uninitialized data */
static u32 __tcmdata tcmvar;
/* Initialized data */
static u32 __tcmdata tcmassigned = 0x2BADBABEU;
/* Constant */
static const u32 __tcmconst tcmconst = 0xCAFEBABEU;

static void __tcmlocalfunc tcm_to_tcm(void)
{
	int i;
	for (i = 0; i < 100; i++)
		tcmvar ++;
}

static void __tcmfunc hello_tcm(void)
{
	/* Some abstract code that runs in ITCM */
	int i;
	for (i = 0; i < 100; i++) {
		tcmvar ++;
	}
	tcm_to_tcm();
}

static void __init test_tcm(void)
{
	u32 *tcmem;
	int i;

	hello_tcm();
	printk("Hello TCM executed from ITCM RAM\n");

	printk("TCM variable from testrun: %u @ %p\n", tcmvar, &tcmvar);
	tcmvar = 0xDEADBEEFU;
	printk("TCM variable: 0x%x @ %p\n", tcmvar, &tcmvar);

	printk("TCM assigned variable: 0x%x @ %p\n", tcmassigned, &tcmassigned);

	printk("TCM constant: 0x%x @ %p\n", tcmconst, &tcmconst);

	/* Allocate some TCM memory from the pool */
	tcmem = tcm_alloc(20);
	if (tcmem) {
		printk("TCM Allocated 20 bytes of TCM @ %p\n", tcmem);
		tcmem[0] = 0xDEADBEEFU;
		tcmem[1] = 0x2BADBABEU;
		tcmem[2] = 0xCAFEBABEU;
		tcmem[3] = 0xDEADBEEFU;
		tcmem[4] = 0x2BADBABEU;
		for (i = 0; i < 5; i++)
			printk("TCM tcmem[%d] = %08x\n", i, tcmem[i]);
		tcm_free(tcmem, 20);
	}
}

TODO:
 - Separate fixup mapping from highmem
 - Support abiv1

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-02-21 15:43:24 +08:00
Mao Han 2f78c73f78 csky: Initial stack protector support
This is a basic -fstack-protector support without per-task canary
switching. The protector will report something like when stack
corruption is detected:

It's tested with strcpy local array overflow in sys_kill and get:
stack-protector: Kernel stack is corrupted in: sys_kill+0x23c/0x23c

TODO:
 - Support task switch for different cannary

Signed-off-by: Mao Han <han_mao@c-sky.com>
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-02-21 15:43:24 +08:00