| Message ID | 20210115095307.12912-1-zhukeqian1@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | kvm: arm64: Properly align the end address of table walk | expand |
On Fri, Jan 15, 2021 at 05:53:07PM +0800, Keqian Zhu wrote: > When align the end address, ought to use its original value. > > Fixes: b1e57de62cfb ("KVM: arm64: Add stand-alone page-table walker infrastructure") > Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com> > --- > arch/arm64/kvm/hyp/pgtable.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c > index bdf8e55ed308..670b0ef12440 100644 > --- a/arch/arm64/kvm/hyp/pgtable.c > +++ b/arch/arm64/kvm/hyp/pgtable.c > @@ -296,7 +296,7 @@ int kvm_pgtable_walk(struct kvm_pgtable *pgt, u64 addr, u64 size, > struct kvm_pgtable_walk_data walk_data = { > .pgt = pgt, > .addr = ALIGN_DOWN(addr, PAGE_SIZE), > - .end = PAGE_ALIGN(walk_data.addr + size), > + .end = PAGE_ALIGN(addr + size), > .walker = walker, Hmm, this is a change in behaviour, no (consider the case where both 'addr' and 'size' are misaligned)? The current code is consistent with the kerneldoc in asm/kvm_pgtable.h, so I don't see the motivation to change it. Did you hit a bug somewhere? Will
On 2021/1/15 18:23, Will Deacon wrote: > On Fri, Jan 15, 2021 at 05:53:07PM +0800, Keqian Zhu wrote: >> When align the end address, ought to use its original value. >> >> Fixes: b1e57de62cfb ("KVM: arm64: Add stand-alone page-table walker infrastructure") >> Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com> >> --- >> arch/arm64/kvm/hyp/pgtable.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c >> index bdf8e55ed308..670b0ef12440 100644 >> --- a/arch/arm64/kvm/hyp/pgtable.c >> +++ b/arch/arm64/kvm/hyp/pgtable.c >> @@ -296,7 +296,7 @@ int kvm_pgtable_walk(struct kvm_pgtable *pgt, u64 addr, u64 size, >> struct kvm_pgtable_walk_data walk_data = { >> .pgt = pgt, >> .addr = ALIGN_DOWN(addr, PAGE_SIZE), >> - .end = PAGE_ALIGN(walk_data.addr + size), >> + .end = PAGE_ALIGN(addr + size), >> .walker = walker, > > Hmm, this is a change in behaviour, no (consider the case where both 'addr' > and 'size' are misaligned)? The current code is consistent with the > kerneldoc in asm/kvm_pgtable.h, so I don't see the motivation to change it. > > Did you hit a bug somewhere? > > Will > . > Not hit a bug, I just read the code to implement a new idea of stage2 DBM support [1]. Yes, according to doc, this is not an issue ("The offset of @addr within a page is ignored."). Sorry to disturb ;-). [1] https://lore.kernel.org/kvmarm/fd26654b-8258-061c-2a69-90b961c1c71b@huawei.com/ Thanks, Keqian
diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c index bdf8e55ed308..670b0ef12440 100644 --- a/arch/arm64/kvm/hyp/pgtable.c +++ b/arch/arm64/kvm/hyp/pgtable.c @@ -296,7 +296,7 @@ int kvm_pgtable_walk(struct kvm_pgtable *pgt, u64 addr, u64 size, struct kvm_pgtable_walk_data walk_data = { .pgt = pgt, .addr = ALIGN_DOWN(addr, PAGE_SIZE), - .end = PAGE_ALIGN(walk_data.addr + size), + .end = PAGE_ALIGN(addr + size), .walker = walker, };
When align the end address, ought to use its original value. Fixes: b1e57de62cfb ("KVM: arm64: Add stand-alone page-table walker infrastructure") Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com> --- arch/arm64/kvm/hyp/pgtable.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)