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NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | STANDARDS | HISTORY | EXAMPLES | SEE ALSO | COLOPHON |
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UFFDIO_POISON(2const) UFFDIO_POISON(2const)
UFFDIO_POISON - mark an address range as "poisoned"
Standard C library (libc, -lc)
#include <linux/userfaultfd.h> /* Definition of UFFD* constants */
#include <sys/ioctl.h>
int ioctl(int fd, UFFDIO_POISON, ...);
#include <linux/userfaultfd.h>
struct uffdio_poison {
struct uffdio_range range;
/* Range to install poison PTE markers in */
__u64 mode; /* Flags controlling the behavior of poison */
__s64 updated; /* Number of bytes poisoned, or negated error */
};
Mark an address range as "poisoned". Future accesses to these
addresses will raise a SIGBUS signal. Unlike MADV_HWPOISON this
works by installing page table entries, rather than "really"
poisoning the underlying physical pages. This means it only
affects this particular address space.
The following value may be bitwise ORed in mode to change the
behavior of the UFFDIO_POISON operation:
UFFDIO_POISON_MODE_DONTWAKE
Do not wake up the thread that waits for page-fault
resolution.
The updated field is used by the kernel to return the number of
bytes that were actually poisoned, or an error in the same manner
as UFFDIO_COPY. If the value returned in the updated field
doesn't match the value that was specified in range.len, the
operation fails with the error EAGAIN. The updated field is
output-only; it is not read by the UFFDIO_POISON operation.
On success, 0 is returned. In this case, the entire area was
poisoned.
On error, -1 is returned and errno is set to indicate the error.
EAGAIN The number of bytes mapped (i.e., the value returned in
the updated field) does not equal the value that was
specified in the range.len field.
EINVAL Either range.start or range.len was not a multiple of the
system page size; or range.len was zero; or the range
specified was invalid.
EINVAL An invalid bit was specified in the mode field.
EEXIST One or more pages were already mapped in the given range.
ENOENT The faulting process has changed its virtual memory layout
simultaneously with an outstanding UFFDIO_POISON
operation.
ENOMEM Allocating memory for page table entries failed.
ESRCH The faulting process has exited at the time of a
UFFDIO_POISON operation.
Linux.
Linux 6.6.
See userfaultfd(2).
ioctl(2), ioctl_userfaultfd(2), userfaultfd(2)
linux.git/Documentation/admin-guide/mm/userfaultfd.rst
This page is part of the man-pages (Linux kernel and C library
user-space interface documentation) project. Information about
the project can be found at
⟨https://www.kernel.org/doc/man-pages/⟩. If you have a bug report
for this manual page, see
⟨https://git.kernel.org/pub/scm/docs/man-pages/man-pages.git/tree/CONTRIBUTING⟩.
This page was obtained from the tarball man-pages-6.9.1.tar.gz
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⟨https://mirrors.edge.kernel.org/pub/linux/docs/man-pages/⟩ on
2024-06-26. If you discover any rendering problems in this HTML
version of the page, or you believe there is a better or more up-
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[email protected]
Linux man-pages 6.9.1 2024-06-17 UFFDIO_POISON(2const)
Pages that refer to this page: ioctl_userfaultfd(2)
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HTML rendering created 2024-06-26 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
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