On Thu, Apr 14, 2022 at 11:44:42AM -0600, Theo de Raadt wrote:
> > If I understand correctly, the problem is that writing to memory
> > of an mmap(2)ed file has no error handling. If the file system is
> > full, userland cannot be informed. So someone invented this message
> > in the kernel.
>
> If you cannot return an error to the program, deciding to print a message
> to the console doesn't fix anything. The program doesn't see the problem.
> The program cannot cope. The user sees an irrelevant message which doesn't
> give them any action they can take. Not even root will know what to do.
ok to delete the message?
bluhm
Index: uvm/uvm_vnode.c
===================================================================
RCS file: /data/mirror/openbsd/cvs/src/sys/uvm/uvm_vnode.c,v
retrieving revision 1.121
diff -u -p -r1.121 uvm_vnode.c
--- uvm/uvm_vnode.c 15 Dec 2021 12:53:53 -0000 1.121
+++ uvm/uvm_vnode.c 14 Apr 2022 17:34:01 -0000
@@ -744,7 +744,7 @@ ReTry:
*/
#ifdef DIAGNOSTIC
if (flags & PGO_SYNCIO)
- panic("uvn_flush: PGO_SYNCIO return 'try again' error (impossible)");
+ panic("%s: PGO_SYNCIO return 'try again' error (impossible)", __func__);
#endif
flags |= PGO_SYNCIO;
if (flags & PGO_FREE)
@@ -807,17 +807,8 @@ ReTry:
}
} else if (flags & PGO_FREE &&
result != VM_PAGER_PEND) {
- if (result != VM_PAGER_OK) {
- printf("uvn_flush: obj=%p, "
- "offset=0x%llx. error "
- "during pageout.\n",
- pp->uobject,
- (long long)pp->offset);
- printf("uvn_flush: WARNING: "
- "changes to page may be "
- "lost!\n");
+ if (result != VM_PAGER_OK)
retval = FALSE;
- }
pmap_page_protect(ptmp, PROT_NONE);
uvm_pageclean(ptmp);
TAILQ_INSERT_TAIL(&dead, ptmp, pageq);
