| Message ID | 20220721121319.2999259-1-xukuohai@huaweicloud.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [bpf-next] bpf, arm64: Fix compile error in dummy_tramp() | expand |
On Thu, Jul 21, 2022 at 08:13:19AM -0400, Xu Kuohai wrote: > From: Xu Kuohai <xukuohai@huawei.com> > > dummy_tramp() uses "lr" to refer to the x30 register, but some assembler > does not recognize "lr" and reports a build failure: > > /tmp/cc52xO0c.s: Assembler messages: > /tmp/cc52xO0c.s:8: Error: operand 1 should be an integer register -- `mov lr,x9' > /tmp/cc52xO0c.s:7: Error: undefined symbol lr used as an immediate value > make[2]: *** [scripts/Makefile.build:250: arch/arm64/net/bpf_jit_comp.o] Error 1 > make[1]: *** [scripts/Makefile.build:525: arch/arm64/net] Error 2 > > So replace "lr" with "x30" to fix it. > > Fixes: b2ad54e1533e ("bpf, arm64: Implement bpf_arch_text_poke() for arm64") > Reported-by: Jon Hunter <jonathanh@nvidia.com> > Tested-by: Jon Hunter <jonathanh@nvidia.com> > Signed-off-by: Xu Kuohai <xukuohai@huawei.com> Jean-Philippe, could you please take a look? thanks, jirka > --- > arch/arm64/net/bpf_jit_comp.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c > index dcc572b7d4da..7ca8779ae34f 100644 > --- a/arch/arm64/net/bpf_jit_comp.c > +++ b/arch/arm64/net/bpf_jit_comp.c > @@ -610,8 +610,8 @@ asm ( > #if IS_ENABLED(CONFIG_ARM64_BTI_KERNEL) > " bti j\n" /* dummy_tramp is called via "br x10" */ > #endif > -" mov x10, lr\n" > -" mov lr, x9\n" > +" mov x10, x30\n" > +" mov x30, x9\n" > " ret x10\n" > " .size dummy_tramp, .-dummy_tramp\n" > " .popsection\n" > -- > 2.30.2 >
On Thu, Jul 21, 2022 at 08:13:19AM -0400, Xu Kuohai wrote: > From: Xu Kuohai <xukuohai@huawei.com> > > dummy_tramp() uses "lr" to refer to the x30 register, but some assembler > does not recognize "lr" and reports a build failure: > > /tmp/cc52xO0c.s: Assembler messages: > /tmp/cc52xO0c.s:8: Error: operand 1 should be an integer register -- `mov lr,x9' > /tmp/cc52xO0c.s:7: Error: undefined symbol lr used as an immediate value > make[2]: *** [scripts/Makefile.build:250: arch/arm64/net/bpf_jit_comp.o] Error 1 > make[1]: *** [scripts/Makefile.build:525: arch/arm64/net] Error 2 > > So replace "lr" with "x30" to fix it. > > Fixes: b2ad54e1533e ("bpf, arm64: Implement bpf_arch_text_poke() for arm64") > Reported-by: Jon Hunter <jonathanh@nvidia.com> > Tested-by: Jon Hunter <jonathanh@nvidia.com> > Signed-off-by: Xu Kuohai <xukuohai@huawei.com> Right, it looks like the lr alias was only added to binutils 2.30, and Linux supports 2.23+ Reviewed-by: Jean-Philippe Brucker <jean-philippe@linaro.org> > --- > arch/arm64/net/bpf_jit_comp.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c > index dcc572b7d4da..7ca8779ae34f 100644 > --- a/arch/arm64/net/bpf_jit_comp.c > +++ b/arch/arm64/net/bpf_jit_comp.c > @@ -610,8 +610,8 @@ asm ( > #if IS_ENABLED(CONFIG_ARM64_BTI_KERNEL) > " bti j\n" /* dummy_tramp is called via "br x10" */ > #endif > -" mov x10, lr\n" > -" mov lr, x9\n" > +" mov x10, x30\n" > +" mov x30, x9\n" > " ret x10\n" > " .size dummy_tramp, .-dummy_tramp\n" > " .popsection\n" > -- > 2.30.2 >
Hello: This patch was applied to bpf/bpf-next.git (master) by Daniel Borkmann <daniel@iogearbox.net>: On Thu, 21 Jul 2022 08:13:19 -0400 you wrote: > From: Xu Kuohai <xukuohai@huawei.com> > > dummy_tramp() uses "lr" to refer to the x30 register, but some assembler > does not recognize "lr" and reports a build failure: > > /tmp/cc52xO0c.s: Assembler messages: > /tmp/cc52xO0c.s:8: Error: operand 1 should be an integer register -- `mov lr,x9' > /tmp/cc52xO0c.s:7: Error: undefined symbol lr used as an immediate value > make[2]: *** [scripts/Makefile.build:250: arch/arm64/net/bpf_jit_comp.o] Error 1 > make[1]: *** [scripts/Makefile.build:525: arch/arm64/net] Error 2 > > [...] Here is the summary with links: - [bpf-next] bpf, arm64: Fix compile error in dummy_tramp() https://git.kernel.org/bpf/bpf-next/c/339ed900b307 You are awesome, thank you!
diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c index dcc572b7d4da..7ca8779ae34f 100644 --- a/arch/arm64/net/bpf_jit_comp.c +++ b/arch/arm64/net/bpf_jit_comp.c @@ -610,8 +610,8 @@ asm ( #if IS_ENABLED(CONFIG_ARM64_BTI_KERNEL) " bti j\n" /* dummy_tramp is called via "br x10" */ #endif -" mov x10, lr\n" -" mov lr, x9\n" +" mov x10, x30\n" +" mov x30, x9\n" " ret x10\n" " .size dummy_tramp, .-dummy_tramp\n" " .popsection\n"