| Age | Commit message (Collapse) | Author |
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After a recent change in clang to strengthen uninitialized warnings [1],
there is a warning from val being uninitialized in __put_user_nocheck
when called from futex_put_value():
kernel/futex/futex.h:326:18: warning: variable 'val' is uninitialized when used within its own initialization [-Wuninitialized]
326 | unsafe_put_user(val, to, Efault);
| ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~
arch/riscv/include/asm/uaccess.h:464:21: note: expanded from macro 'unsafe_put_user'
464 | __put_user_nocheck(x, (ptr), label)
| ~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~
arch/riscv/include/asm/uaccess.h:314:36: note: expanded from macro '__put_user_nocheck'
314 | __inttype(x) val = (__inttype(x))x; \
| ~~~ ^
While not on by default, -Wshadow flags the same mistake:
kernel/futex/futex.h:326:2: warning: declaration shadows a local variable [-Wshadow]
326 | unsafe_put_user(val, to, Efault);
| ^
arch/riscv/include/asm/uaccess.h:464:2: note: expanded from macro 'unsafe_put_user'
464 | __put_user_nocheck(x, (ptr), label)
| ^
arch/riscv/include/asm/uaccess.h:314:16: note: expanded from macro '__put_user_nocheck'
314 | __inttype(x) val = (__inttype(x))x; \
| ^
kernel/futex/futex.h:320:48: note: previous declaration is here
320 | static __always_inline int futex_put_value(u32 val, u32 __user *to)
| ^
Use a three underscore prefix for the val variable in __put_user_nocheck
to avoid clashing with either val or __val, which are both used within
the put_user macros, clearing up all warnings.
Closes: https://github.com/ClangBuiltLinux/linux/issues/2109
Fixes: ca1a66cdd685 ("riscv: uaccess: do not do misaligned accesses in get/put_user()")
Link: https://github.com/llvm/llvm-project/commit/2464313eef01c5b1edf0eccf57a32cdee01472c7 [1]
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20250715-riscv-uaccess-fix-self-init-val-v1-1-82b8e911f120@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
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I must have lost this rebasing things during the merge window, I know I
got it at some point but it's not here now. Without this I get warnings
along the lines of
include/linux/fs.h:3975:15: warning: label followed by a declaration is a C23 extension [-Wc23-extensions]
3975 | if (unlikely(get_user(c, path)))
| ^
arch/riscv/include/asm/uaccess.h:274:3: note: expanded from macro 'get_user'
274 | __get_user((x), __p) : \
| ^
arch/riscv/include/asm/uaccess.h:244:2: note: expanded from macro '__get_user'
244 | __get_user_error(__gu_val, __gu_ptr, __gu_err); \
| ^
arch/riscv/include/asm/uaccess.h:207:2: note: expanded from macro '__get_user_error'
207 | __ge LD [M] net/802/psnap.ko
t_user_nocheck(x, ptr, __gu_failed); \
| ^
arch/riscv/include/asm/uaccess.h:196:3: note: expanded from macro '__get_user_nocheck'
196 | __get_user_8((x), __gu_ptr, label); \
| ^
arch/riscv/include/asm/uaccess.h:130:2: note: expanded from macro '__get_user_8'
130 | u32 __user *__ptr = (u32 __user *)(ptr); \
| ^
Link: https://lore.kernel.org/r/20250610213058.24852-1-palmer@dabbelt.com
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Cc: stable@vger.kernel.org
Fixes: f6bff7827a48 ("riscv: uaccess: use 'asm_goto_output' for get_user()")
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
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Doing misaligned access to userspace memory would make a trap on
platform where it is emulated. Latest fixes removed the kernel
capability to do unaligned accesses to userspace memory safely since
interrupts are kept disabled at all time during that. Thus doing so
would crash the kernel.
Such behavior was detected with GET_UNALIGN_CTL() that was doing
a put_user() with an unsigned long* address that should have been an
unsigned int*. Reenabling kernel misaligned access emulation is a bit
risky and it would also degrade performances. Rather than doing that,
we will try to avoid any misaligned accessed by using copy_from/to_user()
which does not do any misaligned accesses. This can be done only for
!CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS and thus allows to only generate
a bit more code for this config.
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20250602193918.868962-4-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
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The current implementation is underperforming and in addition, it
triggers misaligned access traps on platforms which do not handle
misaligned accesses in hardware.
Use the existing assembly routines to solve both problems at once.
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20250602193918.868962-2-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
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With 'asm goto' we don't need to test the error etc, the exception just
jumps to the error handling directly.
Unlike put_user(), get_user() must work around GCC bugs [1] when using
output clobbers in an asm goto statement.
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113921 # 1
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
[Cyril Bur: Rewritten commit message]
Signed-off-by: Cyril Bur <cyrilbur@tenstorrent.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20250410070526.3160847-6-cyrilbur@tenstorrent.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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With 'asm goto' we don't need to test the error etc, the exception just
jumps to the error handling directly.
Because there are no output clobbers which could trigger gcc bugs [1]
the use of asm_goto_output() macro is not necessary here. Not using
asm_goto_output() is desirable as the generated output asm will be
cleaner.
Use of the volatile keyword is redundant as per gcc 14.2.0 manual section
6.48.2.7 Goto Labels:
> Also note that an asm goto statement is always implicitly considered
volatile.
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113921 # 1
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
[Cyril Bur: Rewritten commit message]
Signed-off-by: Cyril Bur <cyrilbur@tenstorrent.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20250410070526.3160847-5-cyrilbur@tenstorrent.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Putting ptr in the inputs as opposed to output may seem incorrect but
this is done for a few reasons:
- Not having it in the output permits the use of asm goto in a
subsequent patch. There are bugs in gcc [1] which would otherwise
prevent it.
- Since the output memory is userspace there isn't any real benefit from
telling the compiler about the memory clobber.
- x86, arm and powerpc all use this technique.
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113921 # 1
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
[Cyril Bur: Rewritten commit message]
Signed-off-by: Cyril Bur <cyrilbur@tenstorrent.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20250410070526.3160847-4-cyrilbur@tenstorrent.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Currently, when a function like strncpy_from_user() is called,
the userspace access protection is disabled and enabled
for every word read.
By implementing user_access_begin() and families, the protection
is disabled at the beginning of the copy and enabled at the end.
The __inttype macro is borrowed from x86 implementation.
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Signed-off-by: Cyril Bur <cyrilbur@tenstorrent.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20250410070526.3160847-3-cyrilbur@tenstorrent.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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When pointer masking is enabled for userspace, the kernel can accept
tagged pointers as arguments to some system calls. Allow this by
untagging the pointers in access_ok() and the uaccess routines. The
uaccess routines must peform untagging in software because U-mode and
S-mode have entirely separate pointer masking configurations. In fact,
hardware may not even implement pointer masking for S-mode.
Since the number of tag bits is variable, untagged_addr_remote() needs
to know what PMLEN to use for the remote mm. Therefore, the pointer
masking mode must be the same for all threads sharing an mm. Enforce
this with a lock flag in the mm context, as x86 does for LAM. The flag
gets reset in init_new_context() during fork(), as the new mm is no
longer multithreaded.
Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>
Tested-by: Charlie Jenkins <charlie@rivosinc.com>
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Link: https://lore.kernel.org/r/20241016202814.4061541-6-samuel.holland@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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These macros did not initialize __kr_err, so they could fail even if
the access did not fault.
Cc: stable@vger.kernel.org
Fixes: d464118cdc41 ("riscv: implement __get_kernel_nofault and __put_user_nofault")
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>
Link: https://lore.kernel.org/r/20240312022030.320789-1-samuel.holland@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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If the get_user(x, ptr) has x as a pointer, then the setting
of (x) = 0 is going to produce the following sparse warning,
so fix this by forcing the type of 'x' when access_ok() fails.
fs/aio.c:2073:21: warning: Using plain integer as NULL pointer
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com>
Link: https://lore.kernel.org/r/20221229170545.718264-1-ben-linux@fluff.org
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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There are many different ways that access_ok() is defined across
architectures, but in the end, they all just compare against the
user_addr_max() value or they accept anything.
Provide one definition that works for most architectures, checking
against TASK_SIZE_MAX for user processes or skipping the check inside
of uaccess_kernel() sections.
For architectures without CONFIG_SET_FS(), this should be the fastest
check, as it comes down to a single comparison of a pointer against a
compile-time constant, while the architecture specific versions tend to
do something more complex for historic reasons or get something wrong.
Type checking for __user annotations is handled inconsistently across
architectures, but this is easily simplified as well by using an inline
function that takes a 'const void __user *' argument. A handful of
callers need an extra __user annotation for this.
Some architectures had trick to use 33-bit or 65-bit arithmetic on the
addresses to calculate the overflow, however this simpler version uses
fewer registers, which means it can produce better object code in the
end despite needing a second (statically predicted) branch.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64, asm-generic]
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Stafford Horne <shorne@gmail.com>
Acked-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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Nine architectures are still missing __{get,put}_kernel_nofault:
alpha, ia64, microblaze, nds32, nios2, openrisc, sh, sparc32, xtensa.
Add a generic version that lets everything use the normal
copy_{from,to}_kernel_nofault() code based on these, removing the last
use of get_fs()/set_fs() from architecture-independent code.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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Inspired by commit 2e77a62cb3a6 ("arm64: extable: add a dedicated
uaccess handler"), do similar to riscv to add a dedicated uaccess
exception handler to update registers in exception context and
subsequently return back into the function which faulted, so we remove
the need for fixups specialized to each faulting instruction.
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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This is a riscv port of commit 819771cc2892 ("arm64: extable:
consolidate definitions").
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Similar as other architectures such as arm64, x86 and so on, use
offsets relative to the exception table entry values rather than
absolute addresses for both the exception locationand the fixup.
However, RISCV label difference will actually produce two relocations,
a pair of R_RISCV_ADD32 and R_RISCV_SUB32. Take below simple code for
example:
$ cat test.S
.section .text
1:
nop
.section __ex_table,"a"
.balign 4
.long (1b - .)
.previous
$ riscv64-linux-gnu-gcc -c test.S
$ riscv64-linux-gnu-readelf -r test.o
Relocation section '.rela__ex_table' at offset 0x100 contains 2 entries:
Offset Info Type Sym. Value Sym. Name + Addend
000000000000 000600000023 R_RISCV_ADD32 0000000000000000 .L1^B1 + 0
000000000000 000500000027 R_RISCV_SUB32 0000000000000000 .L0 + 0
The modpost will complain the R_RISCV_SUB32 relocation, so we need to
patch modpost.c to skip this relocation for .rela__ex_table section.
After this patch, the __ex_table section size of defconfig vmlinux is
reduced from 7072 Bytes to 3536 Bytes.
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Consolidate all the __ex_table constuction code with a _ASM_EXTABLE
helper.
There should be no functional change as a result of this patch.
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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This macro is defined but not used, remove it.
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull misc vfs updates from Al Viro:
"Assorted stuff all over the place"
* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
useful constants: struct qstr for ".."
hostfs_open(): don't open-code file_dentry()
whack-a-mole: kill strlen_user() (again)
autofs: should_expire() argument is guaranteed to be positive
apparmor:match_mn() - constify devpath argument
buffer: a small optimization in grow_buffers
get rid of autofs_getpath()
constify dentry argument of dentry_path()/dentry_path_raw()
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The <asm/uaccess.h> header has a problem with put_user(a, ptr) if
the 'a' is not a simple variable, such as a function. This can lead
to the compiler producing code as so:
1: enable_user_access()
2: evaluate 'a' into register 'r'
3: put 'r' to 'ptr'
4: disable_user_acess()
The issue is that 'a' is now being evaluated with the user memory
protections disabled. So we try and force the evaulation by assigning
'x' to __val at the start, and hoping the compiler barriers in
enable_user_access() do the job of ordering step 2 before step 1.
This has shown up in a bug where 'a' sleeps and thus schedules out
and loses the SR_SUM flag. This isn't sufficient to fully fix, but
should reduce the window of opportunity. The first instance of this
we found is in scheudle_tail() where the code does:
$ less -N kernel/sched/core.c
4263 if (current->set_child_tid)
4264 put_user(task_pid_vnr(current), current->set_child_tid);
Here, the task_pid_vnr(current) is called within the block that has
enabled the user memory access. This can be made worse with KASAN
which makes task_pid_vnr() a rather large call with plenty of
opportunity to sleep.
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Reported-by: syzbot+e74b94fe601ab9552d69@syzkaller.appspotmail.com
Suggested-by: Arnd Bergman <arnd@arndb.de>
--
Changes since v1:
- fixed formatting and updated the patch description with more info
Changes since v2:
- fixed commenting on __put_user() (schwab@linux-m68k.org)
Change since v3:
- fixed RFC in patch title. Should be ready to merge.
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
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Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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The copy_from_kernel_nofault() is broken on riscv because the 'dst' and
'src' are mistakenly reversed in __put_kernel_nofault() macro.
copy_to_kernel_nofault:
...
0xffffffe0003159b8 <+30>: sd a4,0(a1) # a1 aka 'src'
Fixes: d464118cdc ("riscv: implement __get_kernel_nofault and __put_user_nofault")
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anup Patel <anup@brainfault.org>
Tested-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
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Stop providing the possibility to override the address space using
set_fs() now that there is no need for that any more.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
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Implement the non-faulting kernel access helpers directly instead of
abusing the uaccess routines under set_fs(KERNEL_DS).
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
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Add new __get_user_nocheck and __put_user_nocheck that switch on the size
and call the actual inline assembly helpers, and move the uaccess enable
/ disable into the actual __get_user and __put_user. This prepares for
natively implementing __get_kernel_nofault and __put_kernel_nofault.
Also don't bother with the deprecated register keyword for the error
return.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
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This reverts commit adccfb1a805ea84d2db38eb53032533279bdaa97.
Now that the generic uaccess by mempcy code handles unaligned addresses
the generic code can be used for all RISC-V CPUs.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
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segment_eq is only used to implement uaccess_kernel. Just open code
uaccess_kernel in the arch uaccess headers and remove one layer of
indirection.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Greentime Hu <green.hu@gmail.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Link: http://lkml.kernel.org/r/20200710135706.537715-5-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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To ensure TASK_SIZE is defined for USER_DS.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Link: http://lkml.kernel.org/r/20200710135706.537715-4-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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It might have the unaligned access exception when trying to exchange data
with user space program. In this case, it failed in tty_ioctl(). Therefore
we should enable uaccess.S for NOMMU mode since the generic code doesn't
handle the unaligned access cases.
0x8013a212 <tty_ioctl+462>: ld a5,460(s1)
[ 0.115279] Oops - load address misaligned [#1]
[ 0.115284] CPU: 0 PID: 29 Comm: sh Not tainted 5.4.0-rc5-00020-gb4c27160d562-dirty #36
[ 0.115294] epc: 000000008013a212 ra : 000000008013a212 sp : 000000008f48dd50
[ 0.115303] gp : 00000000801cac28 tp : 000000008fb80000 t0 : 00000000000000e8
[ 0.115312] t1 : 000000008f58f108 t2 : 0000000000000009 s0 : 000000008f48ddf0
[ 0.115321] s1 : 000000008f8c6220 a0 : 0000000000000001 a1 : 000000008f48dd28
[ 0.115330] a2 : 000000008fb80000 a3 : 00000000801a7398 a4 : 0000000000000000
[ 0.115339] a5 : 0000000000000000 a6 : 000000008f58f0c6 a7 : 000000000000001d
[ 0.115348] s2 : 000000008f8c6308 s3 : 000000008f78b7c8 s4 : 000000008fb834c0
[ 0.115357] s5 : 0000000000005413 s6 : 0000000000000000 s7 : 000000008f58f2b0
[ 0.115366] s8 : 000000008f858008 s9 : 000000008f776818 s10: 000000008f776830
[ 0.115375] s11: 000000008fb840a8 t3 : 1999999999999999 t4 : 000000008f78704c
[ 0.115384] t5 : 0000000000000005 t6 : 0000000000000002
[ 0.115391] status: 0000000200001880 badaddr: 000000008f8c63ec cause: 0000000000000004
[ 0.115401] ---[ end trace 00d490c6a8b6c9ac ]---
This failure could be fixed after this patch applied.
[ 0.002282] Run /init as init process
Initializing random number generator... [ 0.005573] random: dd: uninitialized urandom read (512 bytes read)
done.
Welcome to Buildroot
buildroot login: root
Password:
Jan 1 00:00:00 login[62]: root login on 'ttySIF0'
~ #
Signed-off-by: Greentime Hu <greentime.hu@sifive.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
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The kernel runs in M-mode without using page tables, and thus can't run
bare metal without help from additional firmware.
Most of the patch is just stubbing out code not needed without page
tables, but there is an interesting detail in the signals implementation:
- The normal RISC-V syscall ABI only implements rt_sigreturn as VDSO
entry point, but the ELF VDSO is not supported for nommu Linux.
We instead copy the code to call the syscall onto the stack.
In addition to enabling the nommu code a new defconfig for a small
kernel image that can run in nommu mode on qemu is also provided, to run
a kernel in qemu you can use the following command line:
qemu-system-riscv64 -smp 2 -m 64 -machine virt -nographic \
-kernel arch/riscv/boot/loader \
-drive file=rootfs.ext2,format=raw,id=hd0 \
-device virtio-blk-device,drive=hd0
Contains contributions from Damien Le Moal <Damien.LeMoal@wdc.com>.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anup Patel <anup@brainfault.org>
[paul.walmsley@sifive.com: updated to apply; add CONFIG_MMU guards
around PCI_IOBASE definition to fix build issues; fixed checkpatch
issues; move the PCI_IO_* and VMEMMAP address space macros along
with the others; resolve sparse warning]
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
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Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation version 2 this program is distributed
in the hope that it will be useful but without any warranty without
even the implied warranty of merchantability or fitness for a
particular purpose see the gnu general public license for more
details
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 97 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141901.025053186@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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RISC-V is always little endian.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
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This matches what other heavily used architectures do, and will allow us
to easily use <asm-generic/uaccess.h> for the nommu case.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
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Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
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A memory save operation to 8-byte variable in RV32 is divided into
two sw instructions in the put_user macro. The current fixup returns
execution flow to the second sw instead of the one after it.
This patch fixes this fixup code according to the load access part.
Signed-off-by: Alan Kao<alankao@andestech.com>
Cc: Greentime Hu <greentime@andestech.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
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Every in-kernel use of this function defined it to KERNEL_DS (either as
an actual define, or as an inline function). It's an entirely
historical artifact, and long long long ago used to actually read the
segment selector valueof '%ds' on x86.
Which in the kernel is always KERNEL_DS.
Inspired by a patch from Jann Horn that just did this for a very small
subset of users (the ones in fs/), along with Al who suggested a script.
I then just took it to the logical extreme and removed all the remaining
gunk.
Roughly scripted with
git grep -l '(get_ds())' -- :^tools/ | xargs sed -i 's/(get_ds())/(KERNEL_DS)/'
git grep -lw 'get_ds' -- :^tools/ | xargs sed -i '/^#define get_ds()/d'
plus manual fixups to remove a few unusual usage patterns, the couple of
inline function cases and to fix up a comment that had become stale.
The 'get_ds()' function remains in an x86 kvm selftest, since in user
space it actually does something relevant.
Inspired-by: Jann Horn <jannh@google.com>
Inspired-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.
It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access. But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.
A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model. And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.
This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.
There were a couple of notable cases:
- csky still had the old "verify_area()" name as an alias.
- the iter_iov code had magical hardcoded knowledge of the actual
values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
really used it)
- microblaze used the type argument for a debug printout
but other than those oddities this should be a total no-op patch.
I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something. Any missed conversion should be trivially fixable, though.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Sparse highlighted it, and appears to be a pure bug (from vs to).
./arch/riscv/include/asm/uaccess.h:403:35: warning: incorrect type in argument 1 (different address spaces)
./arch/riscv/include/asm/uaccess.h:403:39: warning: incorrect type in argument 2 (different address spaces)
./arch/riscv/include/asm/uaccess.h:409:37: warning: incorrect type in argument 1 (different address spaces)
./arch/riscv/include/asm/uaccess.h:409:41: warning: incorrect type in argument 2 (different address spaces)
Signed-off-by: Olof Johansson <olof@lixom.net>
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
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We use a single __copy_user assembly function to copy memory both from
and to userspace. While this works, it triggers sparse errors because
we're implicitly casting between the kernel and user address spaces by
calling __copy_user.
This patch splits the C declaration into a pair of functions,
__asm_copy_{to,from}_user, that have sane semantics WRT __user. This
split make things fine from sparse's point of view. The assembly
implementation keeps a single definition but add a double ENTRY() for it,
one for __asm_copy_to_user and another one for __asm_copy_from_user.
The result is a spare-safe implementation that pays no performance
or code size penalty.
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
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The RISC-V port doesn't suport a nommu mode, so there is no reason
to provide some code only under a CONFIG_MMU ifdef.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
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This patch contains code that is more specific to the RISC-V ISA than it
is to Linux. It contains string and math operations, C wrappers for
various assembly instructions, stack walking code, and uaccess.
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
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