| Message ID | 20171115193414.7678-2-julien.grall@linaro.org |
|---|---|
| State | Accepted |
| Commit | 17a33f943ea93daa7e8c61faad6d1dfd16176761 |
| Headers | show |
| Series | xen/arm: Add more debug in get_page_from_gva | expand |
On Wed, 15 Nov 2017, Julien Grall wrote: > Currently, gvirt_to_maddr return -EFAULT when the translation failed. > It might be useful to return the PAR_EL1 (Physical Address Register) > in such a case to get a better idea of the reason. > > So modify the return value to use 0 on sucess or return the PAR on ^ success > failure. > > The callers are modified to reflect the change of the return value. > > Note that with the change in gvirt_to_maddr, ma needs to be initialized > to avoid GCC been confused (i.e value may be unitialized) with the new ^ uninitialized > construction. > > Signed-off-by: Julien Grall <julien.grall@linaro.org> Acked-by: Stefano Stabellini <sstabellini@kernel.org> I fixed on commit > --- > xen/arch/arm/domain_build.c | 8 ++++---- > xen/arch/arm/kernel.c | 8 ++++---- > xen/arch/arm/p2m.c | 6 +++--- > xen/include/asm-arm/mm.h | 9 +++++++-- > 4 files changed, 18 insertions(+), 13 deletions(-) > > diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c > index bf29299707..c74f4dd69d 100644 > --- a/xen/arch/arm/domain_build.c > +++ b/xen/arch/arm/domain_build.c > @@ -2002,15 +2002,15 @@ static void initrd_load(struct kernel_info *kinfo) > > for ( offs = 0; offs < len; ) > { > - int rc; > - paddr_t s, l, ma; > + uint64_t par; > + paddr_t s, l, ma = 0; > void *dst; > > s = offs & ~PAGE_MASK; > l = min(PAGE_SIZE - s, len); > > - rc = gvirt_to_maddr(load_addr + offs, &ma, GV2M_WRITE); > - if ( rc ) > + par = gvirt_to_maddr(load_addr + offs, &ma, GV2M_WRITE); > + if ( par ) > { > panic("Unable to translate guest address"); > return; > diff --git a/xen/arch/arm/kernel.c b/xen/arch/arm/kernel.c > index c2755a9ab9..a6c6413712 100644 > --- a/xen/arch/arm/kernel.c > +++ b/xen/arch/arm/kernel.c > @@ -167,15 +167,15 @@ static void kernel_zimage_load(struct kernel_info *info) > paddr, load_addr, load_addr + len); > for ( offs = 0; offs < len; ) > { > - int rc; > - paddr_t s, l, ma; > + uint64_t par; > + paddr_t s, l, ma = 0; > void *dst; > > s = offs & ~PAGE_MASK; > l = min(PAGE_SIZE - s, len); > > - rc = gvirt_to_maddr(load_addr + offs, &ma, GV2M_WRITE); > - if ( rc ) > + par = gvirt_to_maddr(load_addr + offs, &ma, GV2M_WRITE); > + if ( par ) > { > panic("Unable to map translate guest address"); > return; > diff --git a/xen/arch/arm/p2m.c b/xen/arch/arm/p2m.c > index 68b488997d..f6b3d8e421 100644 > --- a/xen/arch/arm/p2m.c > +++ b/xen/arch/arm/p2m.c > @@ -1414,7 +1414,7 @@ struct page_info *get_page_from_gva(struct vcpu *v, vaddr_t va, > struct p2m_domain *p2m = p2m_get_hostp2m(d); > struct page_info *page = NULL; > paddr_t maddr = 0; > - int rc; > + uint64_t par; > > /* > * XXX: To support a different vCPU, we would need to load the > @@ -1425,9 +1425,9 @@ struct page_info *get_page_from_gva(struct vcpu *v, vaddr_t va, > > p2m_read_lock(p2m); > > - rc = gvirt_to_maddr(va, &maddr, flags); > + par = gvirt_to_maddr(va, &maddr, flags); > > - if ( rc ) > + if ( par ) > goto err; > > if ( !mfn_valid(maddr_to_mfn(maddr)) ) > diff --git a/xen/include/asm-arm/mm.h b/xen/include/asm-arm/mm.h > index cd6dfb54b9..ad2f2a43dc 100644 > --- a/xen/include/asm-arm/mm.h > +++ b/xen/include/asm-arm/mm.h > @@ -266,11 +266,16 @@ static inline void *maddr_to_virt(paddr_t ma) > } > #endif > > -static inline int gvirt_to_maddr(vaddr_t va, paddr_t *pa, unsigned int flags) > +/* > + * Translate a guest virtual address to a machine address. > + * Return the fault information if the translation has failed else 0. > + */ > +static inline uint64_t gvirt_to_maddr(vaddr_t va, paddr_t *pa, > + unsigned int flags) > { > uint64_t par = gva_to_ma_par(va, flags); > if ( par & PAR_F ) > - return -EFAULT; > + return par; > *pa = (par & PADDR_MASK & PAGE_MASK) | ((unsigned long) va & ~PAGE_MASK); > return 0; > } > -- > 2.11.0 >
diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c index bf29299707..c74f4dd69d 100644 --- a/xen/arch/arm/domain_build.c +++ b/xen/arch/arm/domain_build.c @@ -2002,15 +2002,15 @@ static void initrd_load(struct kernel_info *kinfo) for ( offs = 0; offs < len; ) { - int rc; - paddr_t s, l, ma; + uint64_t par; + paddr_t s, l, ma = 0; void *dst; s = offs & ~PAGE_MASK; l = min(PAGE_SIZE - s, len); - rc = gvirt_to_maddr(load_addr + offs, &ma, GV2M_WRITE); - if ( rc ) + par = gvirt_to_maddr(load_addr + offs, &ma, GV2M_WRITE); + if ( par ) { panic("Unable to translate guest address"); return; diff --git a/xen/arch/arm/kernel.c b/xen/arch/arm/kernel.c index c2755a9ab9..a6c6413712 100644 --- a/xen/arch/arm/kernel.c +++ b/xen/arch/arm/kernel.c @@ -167,15 +167,15 @@ static void kernel_zimage_load(struct kernel_info *info) paddr, load_addr, load_addr + len); for ( offs = 0; offs < len; ) { - int rc; - paddr_t s, l, ma; + uint64_t par; + paddr_t s, l, ma = 0; void *dst; s = offs & ~PAGE_MASK; l = min(PAGE_SIZE - s, len); - rc = gvirt_to_maddr(load_addr + offs, &ma, GV2M_WRITE); - if ( rc ) + par = gvirt_to_maddr(load_addr + offs, &ma, GV2M_WRITE); + if ( par ) { panic("Unable to map translate guest address"); return; diff --git a/xen/arch/arm/p2m.c b/xen/arch/arm/p2m.c index 68b488997d..f6b3d8e421 100644 --- a/xen/arch/arm/p2m.c +++ b/xen/arch/arm/p2m.c @@ -1414,7 +1414,7 @@ struct page_info *get_page_from_gva(struct vcpu *v, vaddr_t va, struct p2m_domain *p2m = p2m_get_hostp2m(d); struct page_info *page = NULL; paddr_t maddr = 0; - int rc; + uint64_t par; /* * XXX: To support a different vCPU, we would need to load the @@ -1425,9 +1425,9 @@ struct page_info *get_page_from_gva(struct vcpu *v, vaddr_t va, p2m_read_lock(p2m); - rc = gvirt_to_maddr(va, &maddr, flags); + par = gvirt_to_maddr(va, &maddr, flags); - if ( rc ) + if ( par ) goto err; if ( !mfn_valid(maddr_to_mfn(maddr)) ) diff --git a/xen/include/asm-arm/mm.h b/xen/include/asm-arm/mm.h index cd6dfb54b9..ad2f2a43dc 100644 --- a/xen/include/asm-arm/mm.h +++ b/xen/include/asm-arm/mm.h @@ -266,11 +266,16 @@ static inline void *maddr_to_virt(paddr_t ma) } #endif -static inline int gvirt_to_maddr(vaddr_t va, paddr_t *pa, unsigned int flags) +/* + * Translate a guest virtual address to a machine address. + * Return the fault information if the translation has failed else 0. + */ +static inline uint64_t gvirt_to_maddr(vaddr_t va, paddr_t *pa, + unsigned int flags) { uint64_t par = gva_to_ma_par(va, flags); if ( par & PAR_F ) - return -EFAULT; + return par; *pa = (par & PADDR_MASK & PAGE_MASK) | ((unsigned long) va & ~PAGE_MASK); return 0; }
Currently, gvirt_to_maddr return -EFAULT when the translation failed. It might be useful to return the PAR_EL1 (Physical Address Register) in such a case to get a better idea of the reason. So modify the return value to use 0 on sucess or return the PAR on failure. The callers are modified to reflect the change of the return value. Note that with the change in gvirt_to_maddr, ma needs to be initialized to avoid GCC been confused (i.e value may be unitialized) with the new construction. Signed-off-by: Julien Grall <julien.grall@linaro.org> --- xen/arch/arm/domain_build.c | 8 ++++---- xen/arch/arm/kernel.c | 8 ++++---- xen/arch/arm/p2m.c | 6 +++--- xen/include/asm-arm/mm.h | 9 +++++++-- 4 files changed, 18 insertions(+), 13 deletions(-)