Re: [PATCH v2] RISC-V: Don't use a global include guard for uapi/asm/syscalls.h
On Wed, 08 Aug 2018 22:58:30 PDT (-0700), Christoph Hellwig wrote: This actually seems to break the compilation for me in for-next: hch@carbon:~/work/linux$ make ARCH=riscv CALLscripts/checksyscalls.sh :1335:2: warning: #warning syscall rseq not implemented [-Wcpp] CHK include/generated/compile.h CC arch/riscv/kernel/syscall_table.o ./arch/riscv/include/uapi/asm/syscalls.h:29:36: error: 'sys_riscv_flush_icache' undeclared here (not in a function); did you mean '__NR_riscv_flush_icache'? __SYSCALL(__NR_riscv_flush_icache, sys_riscv_flush_icache) ^ arch/riscv/kernel/syscall_table.c:21:37: note: in definition of macro '__SYSCALL' #define __SYSCALL(nr, call) [nr] = (call), ^~~~ make[1]: *** [scripts/Makefile.build:318: arch/riscv/kernel/syscall_table.o] Error 1 make: *** [Makefile:1029: arch/riscv/kernel] Error 2 Reverting it for now, but I guess this might hit others too.. Thanks. I dropped this from for-next and just sent out a replacement.
Re: [PATCH v2] RISC-V: Don't use a global include guard for uapi/asm/syscalls.h
This actually seems to break the compilation for me in for-next: hch@carbon:~/work/linux$ make ARCH=riscv CALLscripts/checksyscalls.sh :1335:2: warning: #warning syscall rseq not implemented [-Wcpp] CHK include/generated/compile.h CC arch/riscv/kernel/syscall_table.o ./arch/riscv/include/uapi/asm/syscalls.h:29:36: error: 'sys_riscv_flush_icache' undeclared here (not in a function); did you mean '__NR_riscv_flush_icache'? __SYSCALL(__NR_riscv_flush_icache, sys_riscv_flush_icache) ^ arch/riscv/kernel/syscall_table.c:21:37: note: in definition of macro '__SYSCALL' #define __SYSCALL(nr, call) [nr] = (call), ^~~~ make[1]: *** [scripts/Makefile.build:318: arch/riscv/kernel/syscall_table.o] Error 1 make: *** [Makefile:1029: arch/riscv/kernel] Error 2 Reverting it for now, but I guess this might hit others too..
Re: [PATCH v2] RISC-V: Don't use a global include guard for uapi/asm/syscalls.h
Looks fine (modulo any typos): Reviewed-by: Christoph Hellwig
Re: [PATCH v2] RISC-V: Don't use a global include guard for uapi/asm/syscalls.h
On Mon, 06 Aug 2018 14:00:53 PDT (-0700), rdun...@infradead.org wrote: On 08/06/2018 01:42 PM, Palmer Dabbelt wrote: This file is expected to be included multiple times in the same file in order to allow the __SYSCALL macro to generate system call tables. With a global include guard we end up missing __NR_riscv_flush_icache in the syscall table, which results in icache flushes that escape the vDSO call to not actually do anything. The fix is to move to per-#define include guards, which allows the system call tables to actually be populated. Thanks to Macrus Comstedt for finding and fixing the bug! I also went ahead and fixed the SPDX header to use a //-style comment, which I've been told is the canonical way to do it. Cc: Marcus Comstedt Signed-off-by: Palmer Dabbelt --- arch/riscv/include/asm/unistd.h| 5 + arch/riscv/include/uapi/asm/syscalls.h | 15 +-- 2 files changed, 14 insertions(+), 6 deletions(-) diff --git a/arch/riscv/include/asm/unistd.h b/arch/riscv/include/asm/unistd.h index 080fb28061de..508be1780323 100644 --- a/arch/riscv/include/asm/unistd.h +++ b/arch/riscv/include/asm/unistd.h @@ -11,6 +11,11 @@ * GNU General Public License for more details. */ +/* + * There is explicitly no include guard here because this file is expected to to .. be .. included Thanks. I'm not going to spin a v3 unless there's more feedback, but I'll include it in the PR. + * included multiple times. See uapi/asm/syscalls.h for more info. + */ + #define __ARCH_WANT_SYS_CLONE #include #include diff --git a/arch/riscv/include/uapi/asm/syscalls.h b/arch/riscv/include/uapi/asm/syscalls.h index 818655b0d535..690beb002d1d 100644 --- a/arch/riscv/include/uapi/asm/syscalls.h +++ b/arch/riscv/include/uapi/asm/syscalls.h @@ -1,10 +1,13 @@ -/* SPDX-License-Identifier: GPL-2.0 */ +// SPDX-License-Identifier: GPL-2.0 /* - * Copyright (C) 2017 SiFive + * Copyright (C) 2017-2018 SiFive */ -#ifndef _ASM__UAPI__SYSCALLS_H -#define _ASM__UAPI__SYSCALLS_H +/* + * There is explicitly no include guard here because this file is expected to + * be included multiple times in order to define the syscall macros via like that one :) + * __SYSCALL. + */ /* * Allows the instruction cache to be flushed from userspace. Despite RISC-V
Re: [PATCH v2] RISC-V: Don't use a global include guard for uapi/asm/syscalls.h
On 08/06/2018 01:42 PM, Palmer Dabbelt wrote: > This file is expected to be included multiple times in the same file in > order to allow the __SYSCALL macro to generate system call tables. With > a global include guard we end up missing __NR_riscv_flush_icache in the > syscall table, which results in icache flushes that escape the vDSO call > to not actually do anything. > > The fix is to move to per-#define include guards, which allows the > system call tables to actually be populated. Thanks to Macrus Comstedt > for finding and fixing the bug! > > I also went ahead and fixed the SPDX header to use a //-style comment, > which I've been told is the canonical way to do it. > > Cc: Marcus Comstedt > Signed-off-by: Palmer Dabbelt > --- > arch/riscv/include/asm/unistd.h| 5 + > arch/riscv/include/uapi/asm/syscalls.h | 15 +-- > 2 files changed, 14 insertions(+), 6 deletions(-) > > diff --git a/arch/riscv/include/asm/unistd.h b/arch/riscv/include/asm/unistd.h > index 080fb28061de..508be1780323 100644 > --- a/arch/riscv/include/asm/unistd.h > +++ b/arch/riscv/include/asm/unistd.h > @@ -11,6 +11,11 @@ > * GNU General Public License for more details. > */ > > +/* > + * There is explicitly no include guard here because this file is expected to to .. be .. included > + * included multiple times. See uapi/asm/syscalls.h for more info. > + */ > + > #define __ARCH_WANT_SYS_CLONE > #include > #include > diff --git a/arch/riscv/include/uapi/asm/syscalls.h > b/arch/riscv/include/uapi/asm/syscalls.h > index 818655b0d535..690beb002d1d 100644 > --- a/arch/riscv/include/uapi/asm/syscalls.h > +++ b/arch/riscv/include/uapi/asm/syscalls.h > @@ -1,10 +1,13 @@ > -/* SPDX-License-Identifier: GPL-2.0 */ > +// SPDX-License-Identifier: GPL-2.0 > /* > - * Copyright (C) 2017 SiFive > + * Copyright (C) 2017-2018 SiFive > */ > > -#ifndef _ASM__UAPI__SYSCALLS_H > -#define _ASM__UAPI__SYSCALLS_H > +/* > + * There is explicitly no include guard here because this file is expected to > + * be included multiple times in order to define the syscall macros via like that one :) > + * __SYSCALL. > + */ > > /* > * Allows the instruction cache to be flushed from userspace. Despite RISC-V -- ~Randy
