Re: [PATCH 05/14] uaccess: add generic __{get,put}_kernel_nofault

2022-02-15 Thread Arnd Bergmann 
On Tue, Feb 15, 2022 at 1:31 AM Al Viro  wrote:
>
> On Mon, Feb 14, 2022 at 05:34:43PM +0100, Arnd Bergmann wrote:
> > From: Arnd Bergmann 
> >
> > All architectures that don't provide __{get,put}_kernel_nofault() yet
> > can implement this on top of __{get,put}_user.
> >
> > 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.
>
> I'd put the list of those architectures (AFAICS, that's alpha, ia64,
> microblaze, nds32, nios2, openrisc, sh, sparc32, xtensa) into commit
> message - it's not that hard to find out, but...

done.

> And AFAICS, you've missed nios2 - see
> #define __put_user(x, ptr) put_user(x, ptr)
> in there.  nds32 oddities are dealt with earlier in the series, this
> one is not...

Ok, fixed my bug in nios2 __put_user() as well now. This one is not nearly
as bad as nds32, at least without my patches it should work as expected.

Unfortunately I also noticed that __get_user() on microblaze and nios2
is completely broken for 64-bit arguments, where these copy eight bytes
into a four byte buffer. I'll try to come up with a fix for this as well then.

 Arnd

Re: [PATCH 05/14] uaccess: add generic __{get,put}_kernel_nofault

2022-02-14 Thread Al Viro 
On Mon, Feb 14, 2022 at 05:34:43PM +0100, Arnd Bergmann wrote:
> From: Arnd Bergmann 
> 
> All architectures that don't provide __{get,put}_kernel_nofault() yet
> can implement this on top of __{get,put}_user.
> 
> 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.

I'd put the list of those architectures (AFAICS, that's alpha, ia64,
microblaze, nds32, nios2, openrisc, sh, sparc32, xtensa) into commit
message - it's not that hard to find out, but...

And AFAICS, you've missed nios2 - see
#define __put_user(x, ptr) put_user(x, ptr)
in there.  nds32 oddities are dealt with earlier in the series, this
one is not...

Re: [PATCH 05/14] uaccess: add generic __{get,put}_kernel_nofault

2022-02-14 Thread Christoph Hellwig 
Looks good,

Reviewed-by: Christoph Hellwig

[PATCH 05/14] uaccess: add generic __{get,put}_kernel_nofault

2022-02-14 Thread Arnd Bergmann 
From: Arnd Bergmann 

All architectures that don't provide __{get,put}_kernel_nofault() yet
can implement this on top of __{get,put}_user.

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.

Signed-off-by: Arnd Bergmann 
---
 arch/arm/include/asm/uaccess.h  |   2 -
 arch/arm64/include/asm/uaccess.h|   2 -
 arch/m68k/include/asm/uaccess.h |   2 -
 arch/mips/include/asm/uaccess.h |   2 -
 arch/parisc/include/asm/uaccess.h   |   1 -
 arch/powerpc/include/asm/uaccess.h  |   2 -
 arch/riscv/include/asm/uaccess.h|   2 -
 arch/s390/include/asm/uaccess.h |   2 -
 arch/sparc/include/asm/uaccess_64.h |   2 -
 arch/um/include/asm/uaccess.h   |   2 -
 arch/x86/include/asm/uaccess.h  |   2 -
 include/asm-generic/uaccess.h   |   2 -
 include/linux/uaccess.h |  19 +
 mm/maccess.c| 108 
 14 files changed, 19 insertions(+), 131 deletions(-)

diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h
index 32dbfd81f42a..d20d78c34b94 100644
--- a/arch/arm/include/asm/uaccess.h
+++ b/arch/arm/include/asm/uaccess.h
@@ -476,8 +476,6 @@ do {
\
: "r" (x), "i" (-EFAULT)\
: "cc")
 
-#define HAVE_GET_KERNEL_NOFAULT
-
 #define __get_kernel_nofault(dst, src, type, err_label)
\
 do {   \
const type *__pk_ptr = (src);   \
diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h
index 3a5ff5e20586..2e20879fe3cf 100644
--- a/arch/arm64/include/asm/uaccess.h
+++ b/arch/arm64/include/asm/uaccess.h
@@ -26,8 +26,6 @@
 #include 
 #include 
 
-#define HAVE_GET_KERNEL_NOFAULT
-
 /*
  * Test whether a block of memory is a valid user space address.
  * Returns 1 if the range is valid, 0 otherwise.
diff --git a/arch/m68k/include/asm/uaccess.h b/arch/m68k/include/asm/uaccess.h
index ba670523885c..79617c0b2f91 100644
--- a/arch/m68k/include/asm/uaccess.h
+++ b/arch/m68k/include/asm/uaccess.h
@@ -390,8 +390,6 @@ raw_copy_to_user(void __user *to, const void *from, 
unsigned long n)
 #define INLINE_COPY_FROM_USER
 #define INLINE_COPY_TO_USER
 
-#define HAVE_GET_KERNEL_NOFAULT
-
 #define __get_kernel_nofault(dst, src, type, err_label)
\
 do {   \
type *__gk_dst = (type *)(dst); \
diff --git a/arch/mips/include/asm/uaccess.h b/arch/mips/include/asm/uaccess.h
index f8f74f9f5883..db9a8e002b62 100644
--- a/arch/mips/include/asm/uaccess.h
+++ b/arch/mips/include/asm/uaccess.h
@@ -296,8 +296,6 @@ struct __large_struct { unsigned long buf[100]; };
(val) = __gu_tmp.t; \
 }
 
-#define HAVE_GET_KERNEL_NOFAULT
-
 #define __get_kernel_nofault(dst, src, type, err_label)
\
 do {   \
int __gu_err;   \
diff --git a/arch/parisc/include/asm/uaccess.h 
b/arch/parisc/include/asm/uaccess.h
index ebf8a845b017..0925bbd6db67 100644
--- a/arch/parisc/include/asm/uaccess.h
+++ b/arch/parisc/include/asm/uaccess.h
@@ -95,7 +95,6 @@ struct exception_table_entry {
(val) = (__force __typeof__(*(ptr))) __gu_val;  \
 }
 
-#define HAVE_GET_KERNEL_NOFAULT
 #define __get_kernel_nofault(dst, src, type, err_label)\
 {  \
type __z;   \
diff --git a/arch/powerpc/include/asm/uaccess.h 
b/arch/powerpc/include/asm/uaccess.h
index 63316100080c..a0032c2e7550 100644
--- a/arch/powerpc/include/asm/uaccess.h
+++ b/arch/powerpc/include/asm/uaccess.h
@@ -467,8 +467,6 @@ do {
\
unsafe_put_user(*(u8*)(_src + _i), (u8 __user *)(_dst + _i), 
e); \
 } while (0)
 
-#define HAVE_GET_KERNEL_NOFAULT
-
 #define __get_kernel_nofault(dst, src, type, err_label)
\
__get_user_size_goto(*((type *)(dst)),  \
(__force type __user *)(src), sizeof(type), err_label)
diff --git a/arch/riscv/include/asm/uaccess.h b/arch/riscv/include/asm/uaccess.h
index c701a5e57a2b..4407b9e48d2c 100644
--- a/arch/riscv/include/asm/uaccess.h
+++ b/arch/riscv/include/asm/uaccess.h
@@ -346,8 +346,6 @@ unsigned long __must_check clear_user(void __user *to, 
unsigned long n)
__clear_user(to, n) : n;
 }
 
-#define HAVE_GET_KERNEL_NOFAULT
-
 #define __get_kernel_nofault(dst, src, type, err_label)
\
 d