| From foo@baz Tue May 4 09:25:24 AM CEST 2021 |
| From: Romain Naour <romain.naour@gmail.com> |
| Date: Tue, 20 Apr 2021 22:12:10 +0100 |
| Subject: mips: Do not include hi and lo in clobber list for R6 |
| |
| From: Romain Naour <romain.naour@gmail.com> |
| |
| commit 1d7ba0165d8206ac073f7ac3b14fc0836b66eae7 upstream |
| |
| >From [1] |
| "GCC 10 (PR 91233) won't silently allow registers that are not |
| architecturally available to be present in the clobber list anymore, |
| resulting in build failure for mips*r6 targets in form of: |
| ... |
| .../sysdep.h:146:2: error: the register ‘lo’ cannot be clobbered in ‘asm’ for the current target |
| 146 | __asm__ volatile ( \ |
| | ^~~~~~~ |
| |
| This is because base R6 ISA doesn't define hi and lo registers w/o DSP |
| extension. This patch provides the alternative clobber list for r6 targets |
| that won't include those registers." |
| |
| Since kernel 5.4 and mips support for generic vDSO [2], the kernel fail to |
| build for mips r6 cpus with gcc 10 for the same reason as glibc. |
| |
| [1] https://sourceware.org/git/?p=glibc.git;a=commit;h=020b2a97bb15f807c0482f0faee2184ed05bcad8 |
| [2] '24640f233b46 ("mips: Add support for generic vDSO")' |
| |
| Signed-off-by: Romain Naour <romain.naour@gmail.com> |
| Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> |
| Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> |
| Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| arch/mips/vdso/gettimeofday.c | 14 ++++++++++++-- |
| 1 file changed, 12 insertions(+), 2 deletions(-) |
| |
| --- a/arch/mips/vdso/gettimeofday.c |
| +++ b/arch/mips/vdso/gettimeofday.c |
| @@ -18,6 +18,12 @@ |
| #include <asm/unistd.h> |
| #include <asm/vdso.h> |
| |
| +#if MIPS_ISA_REV < 6 |
| +#define VDSO_SYSCALL_CLOBBERS "hi", "lo", |
| +#else |
| +#define VDSO_SYSCALL_CLOBBERS |
| +#endif |
| + |
| #ifdef CONFIG_MIPS_CLOCK_VSYSCALL |
| |
| static __always_inline long gettimeofday_fallback(struct timeval *_tv, |
| @@ -34,7 +40,9 @@ static __always_inline long gettimeofday |
| : "=r" (ret), "=r" (error) |
| : "r" (tv), "r" (tz), "r" (nr) |
| : "$1", "$3", "$8", "$9", "$10", "$11", "$12", "$13", |
| - "$14", "$15", "$24", "$25", "hi", "lo", "memory"); |
| + "$14", "$15", "$24", "$25", |
| + VDSO_SYSCALL_CLOBBERS |
| + "memory"); |
| |
| return error ? -ret : ret; |
| } |
| @@ -55,7 +63,9 @@ static __always_inline long clock_gettim |
| : "=r" (ret), "=r" (error) |
| : "r" (clkid), "r" (ts), "r" (nr) |
| : "$1", "$3", "$8", "$9", "$10", "$11", "$12", "$13", |
| - "$14", "$15", "$24", "$25", "hi", "lo", "memory"); |
| + "$14", "$15", "$24", "$25", |
| + VDSO_SYSCALL_CLOBBERS |
| + "memory"); |
| |
| return error ? -ret : ret; |
| } |