| Message ID | 1470841215-24450-1-git-send-email-tamas.lengyel@zentific.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
>>> On 10.08.16 at 17:00, <tamas.lengyel@zentific.com> wrote: > From: Tamas K Lengyel <tamas@tklengyel.com> > > Use __get_gfn_type_access instead of get_gfn_type_access when checking > the hostp2m entries during altp2m mem_access setting and gfn remapping > to avoid a lock conflict which can make dom0 freeze. During mem_access > setting the hp2m is already locked. For gfn remapping we change the flow > to lock the hp2m before locking the ap2m. > > Signed-off-by: Tamas K Lengyel <tamas.lengyel@zentific.com> > Reviewed-by: Razvan Cojocaru <rcojocaru@bitdefender.com> Reviewed-by: Jan Beulich <jbeulich@suse.com>
On Thu, Aug 11, 2016 at 5:57 AM, Jan Beulich <JBeulich@suse.com> wrote: >>>> On 10.08.16 at 17:00, <tamas.lengyel@zentific.com> wrote: >> From: Tamas K Lengyel <tamas@tklengyel.com> >> >> Use __get_gfn_type_access instead of get_gfn_type_access when checking >> the hostp2m entries during altp2m mem_access setting and gfn remapping >> to avoid a lock conflict which can make dom0 freeze. During mem_access >> setting the hp2m is already locked. For gfn remapping we change the flow >> to lock the hp2m before locking the ap2m. >> >> Signed-off-by: Tamas K Lengyel <tamas.lengyel@zentific.com> >> Reviewed-by: Razvan Cojocaru <rcojocaru@bitdefender.com> > > Reviewed-by: Jan Beulich <jbeulich@suse.com> Patch ping, I think this just needs George's ack. Tamas
On Wed, Aug 10, 2016 at 4:00 PM, Tamas K Lengyel <tamas.lengyel@zentific.com> wrote: > From: Tamas K Lengyel <tamas@tklengyel.com> > > Use __get_gfn_type_access instead of get_gfn_type_access when checking > the hostp2m entries during altp2m mem_access setting and gfn remapping > to avoid a lock conflict which can make dom0 freeze. During mem_access > setting the hp2m is already locked. For gfn remapping we change the flow > to lock the hp2m before locking the ap2m. > > Signed-off-by: Tamas K Lengyel <tamas.lengyel@zentific.com> > Reviewed-by: Razvan Cojocaru <rcojocaru@bitdefender.com> Acked-by: George Dunlap <george.dunlap@citrix.com> > --- > Cc: George Dunlap <george.dunlap@eu.citrix.com> > Cc: Jan Beulich <jbeulich@suse.com> > Cc: Andrew Cooper <andrew.cooper3@citrix.com> > > v2: Lock the hp2m during gfn remapping > --- > xen/arch/x86/mm/p2m.c | 10 ++++++---- > 1 file changed, 6 insertions(+), 4 deletions(-) > > diff --git a/xen/arch/x86/mm/p2m.c b/xen/arch/x86/mm/p2m.c > index 812dbf6..1eeb934 100644 > --- a/xen/arch/x86/mm/p2m.c > +++ b/xen/arch/x86/mm/p2m.c > @@ -1787,8 +1787,8 @@ int p2m_set_altp2m_mem_access(struct domain *d, struct p2m_domain *hp2m, > if ( !mfn_valid(mfn) ) > { > > - mfn = get_gfn_type_access(hp2m, gfn_l, &t, &old_a, > - P2M_ALLOC | P2M_UNSHARE, &page_order); > + mfn = __get_gfn_type_access(hp2m, gfn_l, &t, &old_a, > + P2M_ALLOC | P2M_UNSHARE, &page_order, 0); > > rc = -ESRCH; > if ( !mfn_valid(mfn) || t != p2m_ram_rw ) > @@ -2548,6 +2548,7 @@ int p2m_change_altp2m_gfn(struct domain *d, unsigned int idx, > hp2m = p2m_get_hostp2m(d); > ap2m = d->arch.altp2m_p2m[idx]; > > + p2m_lock(hp2m); > p2m_lock(ap2m); > > mfn = ap2m->get_entry(ap2m, gfn_x(old_gfn), &t, &a, 0, NULL, NULL); > @@ -2563,8 +2564,8 @@ int p2m_change_altp2m_gfn(struct domain *d, unsigned int idx, > /* Check host p2m if no valid entry in alternate */ > if ( !mfn_valid(mfn) ) > { > - mfn = get_gfn_type_access(hp2m, gfn_x(old_gfn), &t, &a, > - P2M_ALLOC | P2M_UNSHARE, &page_order); > + mfn = __get_gfn_type_access(hp2m, gfn_x(old_gfn), &t, &a, > + P2M_ALLOC | P2M_UNSHARE, &page_order, 0); > > if ( !mfn_valid(mfn) || t != p2m_ram_rw ) > goto out; > @@ -2606,6 +2607,7 @@ int p2m_change_altp2m_gfn(struct domain *d, unsigned int idx, > > out: > p2m_unlock(ap2m); > + p2m_unlock(hp2m); > return rc; > } > > -- > 2.8.1 > > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xen.org > https://lists.xen.org/xen-devel
diff --git a/xen/arch/x86/mm/p2m.c b/xen/arch/x86/mm/p2m.c index 812dbf6..1eeb934 100644 --- a/xen/arch/x86/mm/p2m.c +++ b/xen/arch/x86/mm/p2m.c @@ -1787,8 +1787,8 @@ int p2m_set_altp2m_mem_access(struct domain *d, struct p2m_domain *hp2m, if ( !mfn_valid(mfn) ) { - mfn = get_gfn_type_access(hp2m, gfn_l, &t, &old_a, - P2M_ALLOC | P2M_UNSHARE, &page_order); + mfn = __get_gfn_type_access(hp2m, gfn_l, &t, &old_a, + P2M_ALLOC | P2M_UNSHARE, &page_order, 0); rc = -ESRCH; if ( !mfn_valid(mfn) || t != p2m_ram_rw ) @@ -2548,6 +2548,7 @@ int p2m_change_altp2m_gfn(struct domain *d, unsigned int idx, hp2m = p2m_get_hostp2m(d); ap2m = d->arch.altp2m_p2m[idx]; + p2m_lock(hp2m); p2m_lock(ap2m); mfn = ap2m->get_entry(ap2m, gfn_x(old_gfn), &t, &a, 0, NULL, NULL); @@ -2563,8 +2564,8 @@ int p2m_change_altp2m_gfn(struct domain *d, unsigned int idx, /* Check host p2m if no valid entry in alternate */ if ( !mfn_valid(mfn) ) { - mfn = get_gfn_type_access(hp2m, gfn_x(old_gfn), &t, &a, - P2M_ALLOC | P2M_UNSHARE, &page_order); + mfn = __get_gfn_type_access(hp2m, gfn_x(old_gfn), &t, &a, + P2M_ALLOC | P2M_UNSHARE, &page_order, 0); if ( !mfn_valid(mfn) || t != p2m_ram_rw ) goto out; @@ -2606,6 +2607,7 @@ int p2m_change_altp2m_gfn(struct domain *d, unsigned int idx, out: p2m_unlock(ap2m); + p2m_unlock(hp2m); return rc; }