| Message ID | 1476724859-18818-1-git-send-email-will.deacon@arm.com |
|---|---|
| State | Accepted |
| Commit | 91cb163e4d141c74e99639fbee7c2a6332c92901 |
| Headers | show |
On Mon, Oct 17, 2016 at 06:20:59PM +0100, Will Deacon wrote: > Commit 8a71f0c656e0 ("arm64: sysreg: replace open-coded mrs_s/msr_s with > {read,write}_sysreg_s") introduced a write_sysreg_s macro for writing > to system registers that are not supported by binutils. > > Unfortunately, this was implemented with the wrong template (%0 vs %x0), > so in the case that we are writing a constant 0, we will generate > invalid instruction syntax and bail with a cryptic assembler error: > > | Error: constant expression required > > This patch fixes the template. > > Signed-off-by: Will Deacon <will.deacon@arm.com> Whoops; I should've spotted that in review. FWIW: Acked-by: Mark Rutland <mark.rutland@arm.com> Thanks, Mark. > --- > arch/arm64/include/asm/sysreg.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h > index e8d46e8e6079..6c80b3699cb8 100644 > --- a/arch/arm64/include/asm/sysreg.h > +++ b/arch/arm64/include/asm/sysreg.h > @@ -286,7 +286,7 @@ asm( > > #define write_sysreg_s(v, r) do { \ > u64 __val = (u64)v; \ > - asm volatile("msr_s " __stringify(r) ", %0" : : "rZ" (__val)); \ > + asm volatile("msr_s " __stringify(r) ", %x0" : : "rZ" (__val)); \ > } while (0) > > static inline void config_sctlr_el1(u32 clear, u32 set) > -- > 2.1.4 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h index e8d46e8e6079..6c80b3699cb8 100644 --- a/arch/arm64/include/asm/sysreg.h +++ b/arch/arm64/include/asm/sysreg.h @@ -286,7 +286,7 @@ asm( #define write_sysreg_s(v, r) do { \ u64 __val = (u64)v; \ - asm volatile("msr_s " __stringify(r) ", %0" : : "rZ" (__val)); \ + asm volatile("msr_s " __stringify(r) ", %x0" : : "rZ" (__val)); \ } while (0) static inline void config_sctlr_el1(u32 clear, u32 set)
Commit 8a71f0c656e0 ("arm64: sysreg: replace open-coded mrs_s/msr_s with {read,write}_sysreg_s") introduced a write_sysreg_s macro for writing to system registers that are not supported by binutils. Unfortunately, this was implemented with the wrong template (%0 vs %x0), so in the case that we are writing a constant 0, we will generate invalid instruction syntax and bail with a cryptic assembler error: | Error: constant expression required This patch fixes the template. Signed-off-by: Will Deacon <will.deacon@arm.com> --- arch/arm64/include/asm/sysreg.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- 2.1.4 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel