Commit Graph

16 Commits

Author SHA1 Message Date
Mark Johnston
87382b222f Set OBJ_NOSPLIT on the ksyms(4) VM object.
The object does not provide anonymous memory.

Reported by:	kib
Reviewed by:	kib
MFC after:	3 days
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D22123
2019-10-23 16:53:37 +00:00
Justin Hibbits
8740b33851 ksyms: Fixup symbols for powerpc in the kernel, not just modules
Summary:
PowerPC kernels are fully position independent, just like kernel modules.
The same fixups that are done for modules therefore need to be done to the
kernel, else symbol resolution in, e.g., DTrace, cannot resolve the kernel
symbols, so only addresses in the kernel are printed, while kernel module
symbols are printed.

Test Plan:
Run lockstat on powerpc64.  Note symbols are resolved for kernel and
modules.

Reviewed By: markj
Differential Revision: https://reviews.freebsd.org/D20316
2019-05-20 02:41:09 +00:00
Pedro F. Giffuni
718cf2ccb9 sys/dev: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
2017-11-27 14:52:40 +00:00
Mark Johnston
069555390b Remove D_TRACKCLOSE now that ksyms no longer has a close method.
Reported by:	jhb
X-MFC with:	r321963
2017-08-03 05:55:01 +00:00
Mark Johnston
22e406c80b Rework and simplify the ksyms(4) implementation.
- Store the symbol table contents in an anonymous swap-backed object. Have
  mmap(/dev/ksyms) map that object, and stop mapping the symbol table into
  the calling process in ksyms_open(). Previously we would cache a pointer
  to the pmap of the opening process, and mmap(/dev/ksyms) would create a
  mapping using the physical address found by a pmap lookup at the initial
  mapping address. However, this assumes that the cached pmap is valid,
  which may not be the case. [1]
- Remove the ksyms ioctl interface. It appears to have been added to work
  around a limitation in libelf that no longer exists; see r321842.
  Moreover, the interface is difficult to support and isn't present in
  illumos. Since ksyms was added specifically to support lockstat(1), it
  is expected that this removal won't have any real impact.
- Simplify ksyms_read() to avoid unnecessary copying.
- Don't call the device handle destructor if we fail to capture a snapshot
  of the kernel's symbol table. devfs will do that for us.

Reported by:	Ilja van Sprundel <ivansprundel@ioactive.com> [1]
Reviewed by:	kib (previous revision)
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D11789
2017-08-03 00:38:13 +00:00
Mark Johnston
1e16346226 Fix style bugs in ksyms.c.
No functional change intended.

MFC after:	3 days
2017-07-28 03:18:18 +00:00
Mark Johnston
7c86ae1a00 Restrict permissions on /dev/ksyms to 0400.
The ksyms(4) device was added specifically for use by lockstat(1), which
as a DTrace consumer must run as root.

Discussed with:	emaste
MFC after:	3 days
2017-07-28 03:14:31 +00:00
Hans Petter Selasky
07da61a6cc Streamline use of cdevpriv and correct some corner cases.
1) It is not useful to call "devfs_clear_cdevpriv()" from
"d_close" callbacks, hence for example read, write, ioctl and
so on might be sleeping at the time of "d_close" being called
and then then freed private data can still be accessed.
Examples: dtrace, linux_compat, ksyms (all fixed by this patch)

2) In sys/dev/drm* there are some cases in which memory will
be freed twice, if open fails, first by code in the open
routine, secondly by the cdevpriv destructor. Move registration
of the cdevpriv to the end of the drm open routines.

3) devfs_clear_cdevpriv() is not called if the "d_open" callback
registered cdevpriv data and the "d_open" callback function
returned an error. Fix this.

Discussed with:	phk
MFC after:	2 weeks
2012-08-15 16:19:39 +00:00
Ed Schouten
a185bd12f3 Get rid of D_PSEUDO.
It seems the D_PSEUDO flag was meant to allow make_dev() to return NULL.
Nowadays we have a different interface for that; make_dev_p(). There's
no need to keep it there.

While there, remove an unneeded D_NEEDMINOR from the gpio driver.

Discussed with:	gonzo@ (gpio)
2011-10-18 08:09:44 +00:00
Konstantin Belousov
0f502d1c4e Promote ksyms_map() and ksyms_unmap() to general facility
copyout_map() and copyout_unmap() interfaces.

Submitted by:	John Wehle <john feith com>, nox
MFC after:	2 weeks
2011-03-28 12:48:33 +00:00
Robert Noland
cfd7bacef2 Update d_mmap() to accept vm_ooffset_t and vm_memattr_t.
This replaces d_mmap() with the d_mmap2() implementation and also
changes the type of offset to vm_ooffset_t.

Purge d_mmap2().

All driver modules will need to be rebuilt since D_VERSION is also
bumped.

Reviewed by:	jhb@
MFC after:	Not in this lifetime...
2009-12-29 21:51:28 +00:00
Antoine Brodin
13e403fdea (S)LIST_HEAD_INITIALIZER takes a (S)LIST_HEAD as an argument.
Fix some wrong usages.
Note: this does not affect generated binaries as this argument is not used.

PR:		137213
Submitted by:	Eygene Ryabinkin (initial version)
MFC after:	1 month
2009-12-28 22:56:30 +00:00
Andriy Gapon
e76f11f441 strict kobj signatures: linker_if fixes
in symtab_get method symtab parameter is made constant as this reflects
actual intention and usage of the method

Reviewed by:	imp, current@
Approved by:	jhb (mentor)
2009-06-11 17:05:45 +00:00
John Baldwin
e090d0b63f Remove another d_thread_t use that crept in. 2009-06-01 21:54:22 +00:00
Stacey Son
2f98b86b92 Change from using vm_map_delete() to vm_map_remove().
Approved by:	gnn (mentor)
Obtained from:	kib
2009-05-27 16:20:46 +00:00
Stacey Son
00a5db46de Add the ksyms(4) pseudo driver. The ksyms driver allows a process to
get a quick snapshot of the kernel's symbol table including the symbols
from any loaded modules (the symbols are all merged into one symbol
table).  Unlike like other implementations, this ksyms driver maps
memory in the process memory space to store the snapshot at the time
/dev/ksyms is opened.  It also checks to see if the process has already
a snapshot open and won't allow it to open /dev/ksyms it again until it
closes first.  This prevents kernel and process memory from being
exhausted.  Note that /dev/ksyms is used by the lockstat(1) command.

Reviewed by:	gallatin kib (freebsd-arch)
Approved by:	gnn (mentor)
2009-05-26 21:39:09 +00:00