* [PATCH 1/2] arm:kvm correct prototype to make sparse happy @ 2014-12-22 11:23 Peng Fan 2014-12-22 11:23 ` [PATCH 2/2] arm:kvm remove len 8 for mmio read write buf Peng Fan 0 siblings, 1 reply; 4+ messages in thread From: Peng Fan @ 2014-12-22 11:23 UTC (permalink / raw) To: linux-arm-kernel Warning message: arch/arm/kvm/arm.c:85:17: error: symbol 'kvm_get_running_vcpus' redeclared with different type (originally declared at ./arch/arm/include/asm/kvm_host.h :190) - different address spaces Signed-off-by: Peng Fan <van.freenix@gmail.com> CC: Gleb Natapov <gleb@kernel.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: Christoffer Dall <christoffer.dall@linaro.org> CC: Marc Zyngier <marc.zyngier@arm.com> CC: Russell King <linux@arm.linux.org.uk> --- arch/arm/include/asm/kvm_host.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index 53036e2..219d025 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -187,7 +187,7 @@ static inline void kvm_arch_mmu_notifier_invalidate_page(struct kvm *kvm, } struct kvm_vcpu *kvm_arm_get_running_vcpu(void); -struct kvm_vcpu __percpu **kvm_get_running_vcpus(void); +struct kvm_vcpu * __percpu *kvm_get_running_vcpus(void); int kvm_arm_copy_coproc_indices(struct kvm_vcpu *vcpu, u64 __user *uindices); unsigned long kvm_arm_num_coproc_regs(struct kvm_vcpu *vcpu); -- 1.8.4 ^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH 2/2] arm:kvm remove len 8 for mmio read write buf 2014-12-22 11:23 [PATCH 1/2] arm:kvm correct prototype to make sparse happy Peng Fan @ 2014-12-22 11:23 ` Peng Fan 2014-12-22 11:51 ` Marc Zyngier 0 siblings, 1 reply; 4+ messages in thread From: Peng Fan @ 2014-12-22 11:23 UTC (permalink / raw) To: linux-arm-kernel For arm 32 bit architecture, 8 bytes load/store operation in one instruction will not be generated by compiler. And before invoke mmio_read_buf, there is a piece of code: " len = run->mmio.len; if (len > sizeof(unsigned long)) return -EINVAL; data = mmio_read_buf(run->mmio.data, len); " This piece code also tells that len variable does not exceeds 4 bytes. So, remove 8 bytes assign in mmio_read_buf and mmio_write_buf. Signed-off-by: Peng Fan <van.freenix@gmail.com> CC: Gleb Natapov <gleb@kernel.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: Christoffer Dall <christoffer.dall@linaro.org> CC: Marc Zyngier <marc.zyngier@arm.com> CC: Russell King <linux@arm.linux.org.uk> --- arch/arm/kvm/mmio.c | 10 ---------- 1 file changed, 10 deletions(-) diff --git a/arch/arm/kvm/mmio.c b/arch/arm/kvm/mmio.c index 4cb5a93..953a819 100644 --- a/arch/arm/kvm/mmio.c +++ b/arch/arm/kvm/mmio.c @@ -30,7 +30,6 @@ static void mmio_write_buf(char *buf, unsigned int len, unsigned long data) u8 byte; u16 hword; u32 word; - u64 dword; } tmp; switch (len) { @@ -46,10 +45,6 @@ static void mmio_write_buf(char *buf, unsigned int len, unsigned long data) tmp.word = data; datap = &tmp.word; break; - case 8: - tmp.dword = data; - datap = &tmp.dword; - break; } memcpy(buf, datap, len); @@ -61,7 +56,6 @@ static unsigned long mmio_read_buf(char *buf, unsigned int len) union { u16 hword; u32 word; - u64 dword; } tmp; switch (len) { @@ -76,10 +70,6 @@ static unsigned long mmio_read_buf(char *buf, unsigned int len) memcpy(&tmp.word, buf, len); data = tmp.word; break; - case 8: - memcpy(&tmp.dword, buf, len); - data = tmp.dword; - break; } return data; -- 1.8.4 ^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH 2/2] arm:kvm remove len 8 for mmio read write buf 2014-12-22 11:23 ` [PATCH 2/2] arm:kvm remove len 8 for mmio read write buf Peng Fan @ 2014-12-22 11:51 ` Marc Zyngier 2014-12-22 14:20 ` Peng Fan 0 siblings, 1 reply; 4+ messages in thread From: Marc Zyngier @ 2014-12-22 11:51 UTC (permalink / raw) To: linux-arm-kernel On 22/12/14 11:23, Peng Fan wrote: > For arm 32 bit architecture, 8 bytes load/store operation in one instruction > will not be generated by compiler. Ever heard of lrdr/strd? > And before invoke mmio_read_buf, there is a piece of code: > " > len = run->mmio.len; > if (len > sizeof(unsigned long)) > return -EINVAL; > > data = mmio_read_buf(run->mmio.data, len); > " > > This piece code also tells that len variable does not exceeds 4 bytes. > So, remove 8 bytes assign in mmio_read_buf and mmio_write_buf. NAK. This code is shared between arm and arm64. See commit f42798c. M. > > Signed-off-by: Peng Fan <van.freenix@gmail.com> > CC: Gleb Natapov <gleb@kernel.org> > CC: Paolo Bonzini <pbonzini@redhat.com> > CC: Christoffer Dall <christoffer.dall@linaro.org> > CC: Marc Zyngier <marc.zyngier@arm.com> > CC: Russell King <linux@arm.linux.org.uk> > --- > arch/arm/kvm/mmio.c | 10 ---------- > 1 file changed, 10 deletions(-) > > diff --git a/arch/arm/kvm/mmio.c b/arch/arm/kvm/mmio.c > index 4cb5a93..953a819 100644 > --- a/arch/arm/kvm/mmio.c > +++ b/arch/arm/kvm/mmio.c > @@ -30,7 +30,6 @@ static void mmio_write_buf(char *buf, unsigned int len, unsigned long data) > u8 byte; > u16 hword; > u32 word; > - u64 dword; > } tmp; > > switch (len) { > @@ -46,10 +45,6 @@ static void mmio_write_buf(char *buf, unsigned int len, unsigned long data) > tmp.word = data; > datap = &tmp.word; > break; > - case 8: > - tmp.dword = data; > - datap = &tmp.dword; > - break; > } > > memcpy(buf, datap, len); > @@ -61,7 +56,6 @@ static unsigned long mmio_read_buf(char *buf, unsigned int len) > union { > u16 hword; > u32 word; > - u64 dword; > } tmp; > > switch (len) { > @@ -76,10 +70,6 @@ static unsigned long mmio_read_buf(char *buf, unsigned int len) > memcpy(&tmp.word, buf, len); > data = tmp.word; > break; > - case 8: > - memcpy(&tmp.dword, buf, len); > - data = tmp.dword; > - break; > } > > return data; > -- Jazz is not dead. It just smells funny... ^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH 2/2] arm:kvm remove len 8 for mmio read write buf 2014-12-22 11:51 ` Marc Zyngier @ 2014-12-22 14:20 ` Peng Fan 0 siblings, 0 replies; 4+ messages in thread From: Peng Fan @ 2014-12-22 14:20 UTC (permalink / raw) To: linux-arm-kernel Just began learning this piece of code. Thanks for correcting me. On 12/22/2014 07:51 PM, Marc Zyngier wrote: > On 22/12/14 11:23, Peng Fan wrote: >> For arm 32 bit architecture, 8 bytes load/store operation in one instruction >> will not be generated by compiler. > > Ever heard of lrdr/strd? > >> And before invoke mmio_read_buf, there is a piece of code: >> " >> len = run->mmio.len; >> if (len > sizeof(unsigned long)) >> return -EINVAL; >> >> data = mmio_read_buf(run->mmio.data, len); >> " >> >> This piece code also tells that len variable does not exceeds 4 bytes. >> So, remove 8 bytes assign in mmio_read_buf and mmio_write_buf. > > NAK. This code is shared between arm and arm64. See commit f42798c. > > M. > >> >> Signed-off-by: Peng Fan <van.freenix@gmail.com> >> CC: Gleb Natapov <gleb@kernel.org> >> CC: Paolo Bonzini <pbonzini@redhat.com> >> CC: Christoffer Dall <christoffer.dall@linaro.org> >> CC: Marc Zyngier <marc.zyngier@arm.com> >> CC: Russell King <linux@arm.linux.org.uk> >> --- >> arch/arm/kvm/mmio.c | 10 ---------- >> 1 file changed, 10 deletions(-) >> >> diff --git a/arch/arm/kvm/mmio.c b/arch/arm/kvm/mmio.c >> index 4cb5a93..953a819 100644 >> --- a/arch/arm/kvm/mmio.c >> +++ b/arch/arm/kvm/mmio.c >> @@ -30,7 +30,6 @@ static void mmio_write_buf(char *buf, unsigned int len, unsigned long data) >> u8 byte; >> u16 hword; >> u32 word; >> - u64 dword; >> } tmp; >> >> switch (len) { >> @@ -46,10 +45,6 @@ static void mmio_write_buf(char *buf, unsigned int len, unsigned long data) >> tmp.word = data; >> datap = &tmp.word; >> break; >> - case 8: >> - tmp.dword = data; >> - datap = &tmp.dword; >> - break; >> } >> >> memcpy(buf, datap, len); >> @@ -61,7 +56,6 @@ static unsigned long mmio_read_buf(char *buf, unsigned int len) >> union { >> u16 hword; >> u32 word; >> - u64 dword; >> } tmp; >> >> switch (len) { >> @@ -76,10 +70,6 @@ static unsigned long mmio_read_buf(char *buf, unsigned int len) >> memcpy(&tmp.word, buf, len); >> data = tmp.word; >> break; >> - case 8: >> - memcpy(&tmp.dword, buf, len); >> - data = tmp.dword; >> - break; >> } >> >> return data; >> > > ^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2014-12-22 14:20 UTC | newest] Thread overview: 4+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2014-12-22 11:23 [PATCH 1/2] arm:kvm correct prototype to make sparse happy Peng Fan 2014-12-22 11:23 ` [PATCH 2/2] arm:kvm remove len 8 for mmio read write buf Peng Fan 2014-12-22 11:51 ` Marc Zyngier 2014-12-22 14:20 ` Peng Fan
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