Re: [PATCH v10 1/9] mm: Introduce memfd_restricted system call to create restricted user memory
From: Chao Peng <hidden>
Date: 2023-02-24 05:50:52
Also in:
kvm, linux-arch, linux-doc, linux-fsdevel, linux-mm, lkml, qemu-devel
quoted
int restrictedmem_bind(struct file *file, pgoff_t start, pgoff_t end, struct restrictedmem_notifier *notifier, bool exclusive) { struct restrictedmem *rm = file->f_mapping->private_data; int ret = -EINVAL; down_write(&rm->lock); /* Non-exclusive mappings are not yet implemented. */ if (!exclusive) goto out_unlock; if (!xa_empty(&rm->bindings)) { if (exclusive != rm->exclusive) goto out_unlock; if (exclusive && xa_find(&rm->bindings, &start, end, XA_PRESENT)) goto out_unlock; } xa_store_range(&rm->bindings, start, end, notifier, GFP_KERNEL);|| ld: mm/restrictedmem.o: in function `restrictedmem_bind': mm/restrictedmem.c|295| undefined reference to `xa_store_range'
Right, xa_store_range() is only available for XARRAY_MULTI.
quoted hunk ↗ jump to hunk
This is missing: ===diff --git a/mm/Kconfig b/mm/Kconfig index f952d0172080..03aca542c0da 100644 --- a/mm/Kconfig +++ b/mm/Kconfig@@ -1087,6 +1087,7 @@ config SECRETMEM config RESTRICTEDMEM bool depends on TMPFS + select XARRAY_MULTI=== Thanks,quoted
rm->exclusive = exclusive; ret = 0; out_unlock: up_write(&rm->lock); return ret; } EXPORT_SYMBOL_GPL(restrictedmem_bind); void restrictedmem_unbind(struct file *file, pgoff_t start, pgoff_t end, struct restrictedmem_notifier *notifier) { struct restrictedmem *rm = file->f_mapping->private_data; down_write(&rm->lock); xa_store_range(&rm->bindings, start, end, NULL, GFP_KERNEL); synchronize_rcu(); up_write(&rm->lock); } EXPORT_SYMBOL_GPL(restrictedmem_unbind);-- Alexey