Messages in this thread |  | | Date | Wed, 20 Oct 2021 07:30:07 +0900 | From | Naoya Horiguchi <> | Subject | Re: [v4 PATCH 5/6] mm: shmem: don't truncate page if memory failure happens |
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On Tue, Oct 19, 2021 at 10:29:51AM -0700, Yang Shi wrote: > On Mon, Oct 18, 2021 at 10:52 PM Naoya Horiguchi > <naoya.horiguchi@linux.dev> wrote: > > > > On Thu, Oct 14, 2021 at 12:16:14PM -0700, Yang Shi wrote: ... > > > @@ -2466,7 +2467,15 @@ shmem_write_begin(struct file *file, struct address_space *mapping, > > > return -EPERM; > > > } > > > > > > - return shmem_getpage(inode, index, pagep, SGP_WRITE); > > > + ret = shmem_getpage(inode, index, pagep, SGP_WRITE); > > > + > > > + if (*pagep && PageHWPoison(*pagep)) { > > > > shmem_getpage() could return with pagep == NULL, so you need check ret first > > to avoid NULL pointer dereference. > > Realy? IIUC pagep can't be NULL. It is a pointer's pointer passed in > by the caller, for example, generic_perform_write(). Of course, > "*pagep" could be NULL.
Oh, I simply missed this. You're right. Please ignore my comment on this.
- Naoya Horiguchi
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