diff --git a/drivers/android/binder/page_range.rs b/drivers/android/binder/page_range.rs index e54a90e62402..e82a5523804f 100644 --- a/drivers/android/binder/page_range.rs +++ b/drivers/android/binder/page_range.rs @@ -705,7 +705,7 @@ fn drop(self: Pin<&mut Self>) { let page; let page_index; let mm; - let mmap_read; + let vma_read; let mm_mutex; let vma_addr; let range_ptr; @@ -728,17 +728,18 @@ fn drop(self: Pin<&mut Self>) { None => return LRU_SKIP, }; - mmap_read = match mm.mmap_read_trylock() { - Some(guard) => guard, - None => return LRU_SKIP, - }; - // We can't lock it normally here, since we hold the lru lock. let inner = match range.lock.try_lock() { Some(inner) => inner, None => return LRU_SKIP, }; + vma_addr = inner.vma_addr; + vma_read = match mm.lock_vma_under_rcu(vma_addr) { + Some(guard) => guard, + None => return LRU_SKIP, + }; + // SAFETY: The item is in this lru list, so it's okay to remove it. unsafe { bindings::list_lru_isolate(lru, item) }; @@ -751,7 +752,6 @@ fn drop(self: Pin<&mut Self>) { // `zap_page_range` before we release the mmap lock, so `use_page_slow` will not be able to // insert a new page until after our call to `zap_page_range`. page = unsafe { PageInfo::take_page(info) }; - vma_addr = inner.vma_addr; // From this point on, we don't access this PageInfo or ShrinkablePageRange again, because // they can be freed at any point after we unlock `lru_lock`. This is with the exception of @@ -761,14 +761,12 @@ fn drop(self: Pin<&mut Self>) { // SAFETY: The lru lock is locked when this method is called. unsafe { bindings::spin_unlock(&raw mut (*lru).lock) }; - if let Some(unchecked_vma) = mmap_read.vma_lookup(vma_addr) { - if let Some(vma) = check_vma(unchecked_vma, range_ptr) { - let user_page_addr = vma_addr + (page_index << PAGE_SHIFT); - vma.zap_vma_range(user_page_addr, PAGE_SIZE); - } + if let Some(vma) = check_vma(&vma_read, range_ptr) { + let user_page_addr = vma_addr + (page_index << PAGE_SHIFT); + vma.zap_vma_range(user_page_addr, PAGE_SIZE); } - drop(mmap_read); + drop(vma_read); drop(mm_mutex); drop(mm); drop(page);