| Message ID | 1456870508-20385-1-git-send-email-ross.zwisler@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Mar 01, 2016 at 03:15:08PM -0700, Ross Zwisler wrote: > dax_pfn_mkwrite() previously wasn't checking the return value of the call > to dax_radix_entry(), which was a mistake. > > Instead, capture this return value and pass it up the stack if it is an > error. > */ > - dax_radix_entry(file->f_mapping, vmf->pgoff, NO_SECTOR, false, true); > + error = dax_radix_entry(file->f_mapping, vmf->pgoff, NO_SECTOR, false, > + true); > + if (error) > + return error; > + > return VM_FAULT_NOPAGE; You can't return an errno from here. if (error) return VM_FAULT_SIGBUS; is better. For full points, if (error == -ENOMEM) return VM_FAULT_OOM; if (error) return VM_FAULT_SIGBUS; return VM_FAULT_NOPAGE;
On Wed, Mar 02, 2016 at 09:09:47AM -0500, Matthew Wilcox wrote: > On Tue, Mar 01, 2016 at 03:15:08PM -0700, Ross Zwisler wrote: > > dax_pfn_mkwrite() previously wasn't checking the return value of the call > > to dax_radix_entry(), which was a mistake. > > > > Instead, capture this return value and pass it up the stack if it is an > > error. > > > */ > > - dax_radix_entry(file->f_mapping, vmf->pgoff, NO_SECTOR, false, true); > > + error = dax_radix_entry(file->f_mapping, vmf->pgoff, NO_SECTOR, false, > > + true); > > + if (error) > > + return error; > > + > > return VM_FAULT_NOPAGE; > > You can't return an errno from here. > > if (error) > return VM_FAULT_SIGBUS; > > is better. For full points, > > if (error == -ENOMEM) > return VM_FAULT_OOM; > if (error) > return VM_FAULT_SIGBUS; > return VM_FAULT_NOPAGE; Ah, thank you for catching that.
diff --git a/fs/dax.c b/fs/dax.c index 7111724..5a587dc 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -1056,6 +1056,7 @@ EXPORT_SYMBOL_GPL(dax_pmd_fault); int dax_pfn_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) { struct file *file = vma->vm_file; + int error; /* * We pass NO_SECTOR to dax_radix_entry() because we expect that a @@ -1065,7 +1066,11 @@ int dax_pfn_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) * saves us from having to make a call to get_block() here to look * up the sector. */ - dax_radix_entry(file->f_mapping, vmf->pgoff, NO_SECTOR, false, true); + error = dax_radix_entry(file->f_mapping, vmf->pgoff, NO_SECTOR, false, + true); + if (error) + return error; + return VM_FAULT_NOPAGE; } EXPORT_SYMBOL_GPL(dax_pfn_mkwrite);
dax_pfn_mkwrite() previously wasn't checking the return value of the call to dax_radix_entry(), which was a mistake. Instead, capture this return value and pass it up the stack if it is an error. Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> --- fs/dax.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)