If copyin family of routines fault, kernel does clear PSL.AC on the
fault entry, but the AC flag of the faulted frame is kept intact. Since
onfault handler is effectively jump, AC survives until syscall exit.
Reported by: m00nbsd, via Sony
Reviewed by: markj
Sponsored by: The FreeBSD Foundation
admbugs: 975
Some of them were dereferencing the user pointer before disabling SMAP.
PR: 255591
Reviewed by: kib
Tested by: pitwuu@gmail.com
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D30276
This fixes strace(1) erroneously reporting return values
as "Function not implemented", combined with reporting the binary
ABI as X32.
Very similar code in linux_ptrace_getregs() is left as it is - it's
probably wrong too, but I don't have a way to test it.
Sponsored By: EPSRC
Differential Revision: https://reviews.freebsd.org/D29927
Previously we've returned the error from native ptrace(2), ENOMEM.
This confused Linux strace(2).
Reviewed By: emaste
Sponsored By: EPSRC
Differential Revision: https://reviews.freebsd.org/D29925
This should be a no-op; the purpose of this is to reduce
a spurious difference between Linuxulator and Linux, to make
debugging core dumps slightly easier.
Note that AT_HWCAP2 we pass to Linux binaries is always 0,
instead of being equal to 'cpu_feature2'. This matches what
I've observed under Ubuntu Focal VM.
Reviewed By: chuck, dchagin
Sponsored By: EPSRC
Differential Revision: https://reviews.freebsd.org/D29609
instead of manually inlining it
Reviewed by: jhb
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D29687
- Use update_pcb_bases() when updating FS or GS base addresses to
permit use of FSBASE and GSBASE in Linux processes. This also sets
PCB_FULL_IRET. linux32 was setting PCB_32BIT which should be a
no-op (exec sets it).
- Remove write-only variables to construct unused segment descriptors
for linux32.
Reviewed by: kib
MFC after: 1 week
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D29026
linux_shared_page_init() creates an object and grabs and maps a single
page to back the VDSO. When destroying the VDSO object, we failed to
destroy the mapping and free KVA. Fix this.
Reviewed by: kib
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D28696
The ptrace(2) Linux man page claims the syscall returns ESRCH,
if the tracee is not stopped; the native ptrace(2) returns EBUSY.
Sponsored by: The FreeBSD Foundation
Foundation copyrights, approved by emaste@. It does not include
files which carry other people's copyrights; if you're one
of those people, feel free to make similar change.
Reviewed by: emaste, imp, gbe (manpages)
Differential Revision: https://reviews.freebsd.org/D26980
Linux execve() gets audited as AUE_EXECVE as well, we should also interpret
the return from this correctly for the same reasoning as in r367002.
MFC with: r367002
The former clobbers some registers that shouldn't be touched.
Reviewed by: kib (earlier version)
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D26406
Since LA57 was moved to the main SDM document with revision 072, it
seems that we should have a support for it, and silicons are coming.
This patch makes pmap support both LA48 and LA57 hardware. The
selection of page table level is done at startup, kernel always
receives control from loader with 4-level paging. It is not clear how
UEFI spec would adapt LA57, for instance it could hand out control in
LA57 mode sometimes.
To switch from LA48 to LA57 requires turning off long mode, requesting
LA57 in CR4, then re-entering long mode. This is somewhat delicate
and done in pmap_bootstrap_la57(). AP startup in LA57 mode is much
easier, we only need to toggle a bit in CR4 and load right value in CR3.
I decided to not change kernel map for now. Single PML5 entry is
created that points to the existing kernel_pml4 (KML4Phys) page, and a
pml5 entry to create our recursive mapping for vtopte()/vtopde().
This decision is motivated by the fact that we cannot overcommit for
KVA, so large space there is unusable until machines start providing
wider physical memory addressing. Another reason is that I do not
want to break our fragile autotuning, so the KVA expansion is not
included into this first step. Nice side effect is that minidumps are
compatible.
On the other hand, (very) large address space is definitely
immediately useful for some userspace applications.
For userspace, numbering of pte entries (or page table pages) is
always done for 5-level structures even if we operate in 4-level mode.
The pmap_is_la57() function is added to report the mode of the
specified pmap, this is done not to allow simultaneous 4-/5-levels
(which is not allowed by hw), but to accomodate for EPT which has
separate level control and in principle might not allow 5-leve EPT
despite x86 paging supports it. Anyway, it does not seems critical to
have 5-level EPT support now.
Tested by: pho (LA48 hardware)
Reviewed by: alc
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D25273
This is a step towards facilitating jails with only Linux binaries.
Supporting emul_path adds path lookups which are completely spurious
if the binary at hand runs in a Linux-based root directory.
It defaults to on (== current behavior).
make -C /root/linux-5.3-rc8 -s -j 1 bzImage:
use_emul_path=1: 101.65s user 68.68s system 100% cpu 2:49.62 total
use_emul_path=0: 101.41s user 64.32s system 100% cpu 2:45.02 total
This effectively mirrors our libc implementation, but with minor fudging --
name needs to be copied in from userspace, so we just copy it straight into
stack-allocated memfd_name into the correct position rather than allocating
memory that needs to be cleaned up.
The sealing-related fcntl(2) commands, F_GET_SEALS and F_ADD_SEALS, have
also been implemented now that we support them.
Note that this implementation is still not quite at feature parity w.r.t.
the actual Linux version; some caveats, from my foggy memory:
- Need to implement SHM_GROW_ON_WRITE, default for memfd (in progress)
- LTP wants the memfd name exposed to fdescfs
- Linux allows open() of an fdescfs fd with O_TRUNC to truncate after dup.
(?)
Interested parties can install and run LTP from ports (devel/linux-ltp) to
confirm any fixes.
PR: 240874
Reviewed by: kib, trasz
Differential Revision: https://reviews.freebsd.org/D21845
in vanilla Linux git tree.
Reviewed by: markj
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D25385
FreeBSD madvise(2) directly. While some of the flag values match,
most don't.
PR: kern/230160
Reported by: markj
Reviewed by: markj
Discussed with: brooks, kib
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D25272
Use AUXARGS_ENTRY_PTR to export these pointers. This is a followup to
r359987 and r359988.
Reviewed by: jhb
Obtained from: CheriBSD
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D24446
Copy the CP, PTRIN, etc macros from freebsd32.h into a sys/abi_compat.h
and replace existing definitation with includes where required. This
eliminates duplicate code and allows Linux and FreeBSD compatability
headers to be included in the same files.
Input from: cem, jhb
Obtained from: CheriBSD
MFC after: 2 weeks
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D24275
Submitted by: Bora Özarslan <borako.ozarslan@gmail.com>
Submitted by: Yang Wang <2333@outlook.jp>
Reviewed by: markj
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D19917
