| Message ID | 5721F50602000078000E6ACB@prv-mh.provo.novell.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
> -----Original Message----- > From: Jan Beulich [mailto:JBeulich@suse.com] > Sent: 28 April 2016 10:33 > To: xen-devel > Cc: Paul Durrant; Wei Liu > Subject: [PATCH 2/2] x86/HVM: fix forwarding of internally cached requests > (part 2) > > Commit 96ae556569 ("x86/HVM: fix forwarding of internally cached > requests") wasn't quite complete: hvmemul_do_io() also needs to > propagate up the clipped count. (I really should have re-tested the > forward port resulting in the earlier change, instead of relying on the > testing done on the older version of Xen which the fix was first needed > for.) > > Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Paul Durrant <paul.durrant@citrix.com> > > --- a/xen/arch/x86/hvm/emulate.c > +++ b/xen/arch/x86/hvm/emulate.c > @@ -137,7 +137,7 @@ static int hvmemul_do_io( > if ( (p.type != (is_mmio ? IOREQ_TYPE_COPY : IOREQ_TYPE_PIO)) || > (p.addr != addr) || > (p.size != size) || > - (p.count != *reps) || > + (p.count > *reps) || > (p.dir != dir) || > (p.df != df) || > (p.data_is_ptr != data_is_addr) ) > @@ -145,6 +145,8 @@ static int hvmemul_do_io( > > if ( data_is_addr ) > return X86EMUL_UNHANDLEABLE; > + > + *reps = p.count; > goto finish_access; > default: > return X86EMUL_UNHANDLEABLE; > @@ -162,6 +164,13 @@ static int hvmemul_do_io( > > rc = hvm_io_intercept(&p); > > + /* > + * p.count may have got reduced (see hvm_process_io_intercept()) - > inform > + * our callers and mirror this into latched state. > + */ > + ASSERT(p.count <= *reps); > + *reps = vio->io_req.count = p.count; > + > switch ( rc ) > { > case X86EMUL_OKAY: > >
On 28/04/16 10:33, Jan Beulich wrote: > Commit 96ae556569 ("x86/HVM: fix forwarding of internally cached > requests") wasn't quite complete: hvmemul_do_io() also needs to > propagate up the clipped count. (I really should have re-tested the > forward port resulting in the earlier change, instead of relying on the > testing done on the older version of Xen which the fix was first needed > for.) > > Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
--- a/xen/arch/x86/hvm/emulate.c +++ b/xen/arch/x86/hvm/emulate.c @@ -137,7 +137,7 @@ static int hvmemul_do_io( if ( (p.type != (is_mmio ? IOREQ_TYPE_COPY : IOREQ_TYPE_PIO)) || (p.addr != addr) || (p.size != size) || - (p.count != *reps) || + (p.count > *reps) || (p.dir != dir) || (p.df != df) || (p.data_is_ptr != data_is_addr) ) @@ -145,6 +145,8 @@ static int hvmemul_do_io( if ( data_is_addr ) return X86EMUL_UNHANDLEABLE; + + *reps = p.count; goto finish_access; default: return X86EMUL_UNHANDLEABLE; @@ -162,6 +164,13 @@ static int hvmemul_do_io( rc = hvm_io_intercept(&p); + /* + * p.count may have got reduced (see hvm_process_io_intercept()) - inform + * our callers and mirror this into latched state. + */ + ASSERT(p.count <= *reps); + *reps = vio->io_req.count = p.count; + switch ( rc ) { case X86EMUL_OKAY:
Commit 96ae556569 ("x86/HVM: fix forwarding of internally cached requests") wasn't quite complete: hvmemul_do_io() also needs to propagate up the clipped count. (I really should have re-tested the forward port resulting in the earlier change, instead of relying on the testing done on the older version of Xen which the fix was first needed for.) Signed-off-by: Jan Beulich <jbeulich@suse.com> x86/HVM: fix forwarding of internally cached requests (part 2) Commit 96ae556569 ("x86/HVM: fix forwarding of internally cached requests") wasn't quite complete: hvmemul_do_io() also needs to propagate up the clipped count. (I really should have re-tested the forward port resulting in the earlier change, instead of relying on the testing done on the older version of Xen which the fix was first needed for.) Signed-off-by: Jan Beulich <jbeulich@suse.com> --- a/xen/arch/x86/hvm/emulate.c +++ b/xen/arch/x86/hvm/emulate.c @@ -137,7 +137,7 @@ static int hvmemul_do_io( if ( (p.type != (is_mmio ? IOREQ_TYPE_COPY : IOREQ_TYPE_PIO)) || (p.addr != addr) || (p.size != size) || - (p.count != *reps) || + (p.count > *reps) || (p.dir != dir) || (p.df != df) || (p.data_is_ptr != data_is_addr) ) @@ -145,6 +145,8 @@ static int hvmemul_do_io( if ( data_is_addr ) return X86EMUL_UNHANDLEABLE; + + *reps = p.count; goto finish_access; default: return X86EMUL_UNHANDLEABLE; @@ -162,6 +164,13 @@ static int hvmemul_do_io( rc = hvm_io_intercept(&p); + /* + * p.count may have got reduced (see hvm_process_io_intercept()) - inform + * our callers and mirror this into latched state. + */ + ASSERT(p.count <= *reps); + *reps = vio->io_req.count = p.count; + switch ( rc ) { case X86EMUL_OKAY: