| Message ID | 20191003170423.6221-1-jarkko.sakkinen@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] x86/sgx: Migrate to mmu_notifier_put() | expand |
On Thu, Oct 03, 2019 at 08:04:23PM +0300, Jarkko Sakkinen wrote: > Use mmu_notifier_put() to synchronize sgx_encl_mm deletion. > > Cc: Sean Christopherson <sean.j.christopherson@intel.com> > Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Pushed this already to master. Not squashed yet as I'm compiling a kernel to test it. /Jarkko
On Thu, Oct 03, 2019 at 08:04:23PM +0300, Jarkko Sakkinen wrote: > Use mmu_notifier_put() to synchronize sgx_encl_mm deletion. > > Cc: Sean Christopherson <sean.j.christopherson@intel.com> > Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> > --- > v2: > * Was not thinking clearly that we also use it for lockless > operation on the mm list. Just migrating to mmu_notifier_put(). > Please ignore the previous patch! > arch/x86/kernel/cpu/sgx/encl.c | 26 ++++++++++---------------- > 1 file changed, 10 insertions(+), 16 deletions(-) > > diff --git a/arch/x86/kernel/cpu/sgx/encl.c b/arch/x86/kernel/cpu/sgx/encl.c > index d145360380d5..8cc9ea353bee 100644 > --- a/arch/x86/kernel/cpu/sgx/encl.c > +++ b/arch/x86/kernel/cpu/sgx/encl.c > @@ -131,14 +131,6 @@ static struct sgx_encl_page *sgx_encl_load_page(struct sgx_encl *encl, > return entry; > } > > -static void sgx_encl_mm_release_deferred(struct rcu_head *rcu) > -{ > - struct sgx_encl_mm *encl_mm = > - container_of(rcu, struct sgx_encl_mm, rcu); > - > - kfree(encl_mm); > -} > - > static void sgx_mmu_notifier_release(struct mmu_notifier *mn, > struct mm_struct *mm) > { > @@ -161,19 +153,21 @@ static void sgx_mmu_notifier_release(struct mmu_notifier *mn, > > if (tmp == encl_mm) { > synchronize_srcu(&encl_mm->encl->srcu); > - > - /* > - * Delay freeing encl_mm until after mmu_notifier synchronizes > - * its SRCU to ensure encl_mm cannot be dereferenced. > - */ > - mmu_notifier_unregister_no_release(mn, mm); > - mmu_notifier_call_srcu(&encl_mm->rcu, > - &sgx_encl_mm_release_deferred); > + mmu_notifier_put(mn); > } > } > > +static void sgx_mmu_notifier_free(struct mmu_notifier *mn) > +{ > + struct sgx_encl_mm *encl_mm = > + container_of(mn, struct sgx_encl_mm, mmu_notifier); > + > + kfree(encl_mm); > +} > + > static const struct mmu_notifier_ops sgx_mmu_notifier_ops = { > .release = sgx_mmu_notifier_release, > + .free_notifier = sgx_mmu_notifier_free, > }; > > static struct sgx_encl_mm *sgx_encl_find_mm(struct sgx_encl *encl, > -- > 2.20.1 > This one I squashed (master updated). /Jarkko
diff --git a/arch/x86/kernel/cpu/sgx/encl.c b/arch/x86/kernel/cpu/sgx/encl.c index d145360380d5..8cc9ea353bee 100644 --- a/arch/x86/kernel/cpu/sgx/encl.c +++ b/arch/x86/kernel/cpu/sgx/encl.c @@ -131,14 +131,6 @@ static struct sgx_encl_page *sgx_encl_load_page(struct sgx_encl *encl, return entry; } -static void sgx_encl_mm_release_deferred(struct rcu_head *rcu) -{ - struct sgx_encl_mm *encl_mm = - container_of(rcu, struct sgx_encl_mm, rcu); - - kfree(encl_mm); -} - static void sgx_mmu_notifier_release(struct mmu_notifier *mn, struct mm_struct *mm) { @@ -161,19 +153,21 @@ static void sgx_mmu_notifier_release(struct mmu_notifier *mn, if (tmp == encl_mm) { synchronize_srcu(&encl_mm->encl->srcu); - - /* - * Delay freeing encl_mm until after mmu_notifier synchronizes - * its SRCU to ensure encl_mm cannot be dereferenced. - */ - mmu_notifier_unregister_no_release(mn, mm); - mmu_notifier_call_srcu(&encl_mm->rcu, - &sgx_encl_mm_release_deferred); + mmu_notifier_put(mn); } } +static void sgx_mmu_notifier_free(struct mmu_notifier *mn) +{ + struct sgx_encl_mm *encl_mm = + container_of(mn, struct sgx_encl_mm, mmu_notifier); + + kfree(encl_mm); +} + static const struct mmu_notifier_ops sgx_mmu_notifier_ops = { .release = sgx_mmu_notifier_release, + .free_notifier = sgx_mmu_notifier_free, }; static struct sgx_encl_mm *sgx_encl_find_mm(struct sgx_encl *encl,
Use mmu_notifier_put() to synchronize sgx_encl_mm deletion. Cc: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> --- v2: * Was not thinking clearly that we also use it for lockless operation on the mm list. Just migrating to mmu_notifier_put(). Please ignore the previous patch! arch/x86/kernel/cpu/sgx/encl.c | 26 ++++++++++---------------- 1 file changed, 10 insertions(+), 16 deletions(-)