Commit Graph

211 Commits

Author SHA1 Message Date
Jeff Dike 50f72b5794 [PATCH] uml: fix x86_64 with !CONFIG_FRAME_POINTER
UML/x86_64 doesn't run when built with frame pointers disabled.  There
was an implicit frame pointer assumption in the stub segfault handler.
With frame pointers disabled, UML dies on handling its first page fault.

The container-of part of this is from Paolo Giarrusso <blaisorblade@yahoo.it>.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-10 08:37:59 -07:00
Paolo 'Blaisorblade' Giarrusso 52a2d3e45e [PATCH] uml: cleanup whitespace for COW driver
Fix whitespace - I split this off the previous patch for easier review.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-10 08:36:00 -07:00
Paolo 'Blaisorblade' Giarrusso 028c0cc16e [PATCH] uml: cleanup byte order macros for COW driver
After restoring the existing code, make it work also when included in
kernelspace code (which isn't currently the case, but at least this will prevent
people from "fixing" it as just happened).
Whitespace is fixed in next patch - it cluttered the diff too much.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-10 08:36:00 -07:00
Paolo 'Blaisorblade' Giarrusso 855ec613ca [PATCH] uml: restore include breakage, breaking binary format of COW driver
Commit 44456d37b5, between 2.6.13-rc3 and -rc4,
was a "nice cleanup" which broke something. Revert the offending part.

It broke because:
a) because this part doesn't fall under the description
b) the author didn't know what he was doing here
c) the author didn't try to compile the existing code and see that it worked
   perfectly.
d) the author didn't ask us what was happening
e) you didn't either, and somebody there should have learned that UML is a bit
   different.

In fact, UML is special in linking to host libc and using its includes.

In particular, since host includes always define both __BIG_ENDIAN and
__LITTLE_ENDIAN, ntohll() macros started thinking to be in a big-endian world;
and on-disk compatibility was broken.

Many thanks go to Nix for reporting the problem and correctly diagnosing an
endianness problem.

Btw, this patch restores the previous code, which worked; but the definitions
would be uncorrect if used in kernelspace files.

Next patch addresses that.

Cc: Nix <nix@esperi.org.uk>, Olaf Hering <olh@suse.de>
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-10 08:36:00 -07:00
Paolo 'Blaisorblade' Giarrusso 54a8a2220c [PATCH] uml: allow building .s/.i/.lst files from userspace files
For files which need to include glibc headers (i.e. userspace files), we
specified the correct flags only for .o, not for .s/.lst/.i. Fix this.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-10 08:36:00 -07:00
Paolo 'Blaisorblade' Giarrusso 9e3d862e5c [PATCH] uml: add mode=skas0 as a synonym of skas0
Too many people were confused by skas0 and tried using "mode=skas0". And after
all, they are right - accept this.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-10 08:36:00 -07:00
Paolo 'Blaisorblade' Giarrusso 5cd10daa0c [PATCH] Uml: hide commands when not being verbose
Add a missing $(Q) to a "ln" invocation.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-10 08:36:00 -07:00
Allan Graves fad1c45c93 [PATCH] uml: Fix sysrq-r support for skas mode
The old code had the IP and SP coming from the registers in the thread
struct, which are completely wrong since those are the userspace
registers.  This fixes that by pulling the correct values from the
jmp_buf in which the kernel state of each thread is stored.

Signed-off-by: Allan Graves <allan.graves@oracle.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-04 13:22:01 -07:00
Jeff Dike 71dc036247 [PATCH] UML - Fix Al's build tidying
Al's build tidying missed one bit from me - without this UML doesn't boot.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Acked-by: Al Viro <viro@ftp.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-04 13:22:01 -07:00
Paolo 'Blaisorblade' Giarrusso bd94805735 [PATCH] uml: revert "run mconsole "sysrq" in process context"
Revert commit 12ebcd73e4, i.e.  [PATCH] uml: run
mconsole "sysrq" in process context on request from Jeff Dike.

a) sysrq may be run when the scheduler is non-functioning

b) the warning I wanted to fix actually came from the fault handler run in
   atomic context.  But I fixed that not to take the semaphore in a separate
   patch.

c) the fault handler is run because of a fault, and that fault was
   unaffected by this patch.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-30 12:41:18 -07:00
Paolo 'Blaisorblade' Giarrusso 8923648c12 [PATCH] uml: clear SKAS0/3 flags when running in TT mode
SEGV_MAYBE_FIXABLE tests ptrace_faultinfo, and depends on it being 1 only in
SKAS3 mode, while currently when running with mode=tt it will be 1 anyway.
Fix this, and do the same for proc_mm.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-30 12:41:18 -07:00
Paolo 'Blaisorblade' Giarrusso be662a18b7 [PATCH] uml: fix page faults in SKAS3 mode.
I hadn't been running a SKAS3 host when testing the "uml: fix hang in TT mode
on fault" patch (commit 546fe1cbf9), and I
didn't think enough to the missing trap_no in SKAS3 mode.

In fact, the resulting kernel doesn't work at all in SKAS3 mode.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-30 12:41:18 -07:00
Al Viro 74ba1fd966 [PATCH] useless linux/irq.h includes (arch/um)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-30 08:42:24 -07:00
Al Viro ecba97d4aa [PATCH] uml makefiles sanitized
UML makefiles sanitized:
 - number of generated headers reduced to 2 (from user-offsets.c and
   kernel-offsets.c resp.).  The rest is made constant and simply
   includes those two.
 - mk_... helpers are gone now that we don't need to generate these
   headers
 - arch/um/include2 removed since everything under arch/um/include/sysdep
   is constant now and symlink can point straight to source tree.
 - dependencies seriously simplified.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-29 08:46:26 -07:00
Paolo 'Blaisorblade' Giarrusso fac97ae0b1 [PATCH] uml: replace printk with "stack-friendly" printf - to report console failure
User get *a lot* confused when consoles don't work but we don't report
anything.  And, as reported in the comment, using printk to report "your
console doesn't work" isn't likely to go that far.

Fix the problem on the base of this: stack consumption by host printf().  Use
kernel sprintf() and os_write_file, using a wild guess that one page will be
enough for the message, to preallocate the buffer with kmalloc().

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-22 22:17:37 -07:00
Paolo 'Blaisorblade' Giarrusso 79ae2cb856 [PATCH] uml: use GFP_ATOMIC for allocations under spinlocks.
setup_initial_poll is only called with sigio_lock() held, so use appropriate
allocation.

Also, parse_chan() can also be called when holding a spinlock (see line_open()
 -> parse_chan_pair()).

I have sporadic problems (spinlock taken twice, with spinlock debugging on UP)
which could be caused by a sequence like "take spinlock, alloc and go to
sleep, take again the spinlock in the other thread".

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-22 22:17:37 -07:00
Paolo 'Blaisorblade' Giarrusso 46db4a42dd [PATCH] uml: Fix GFP_ flags usage
GFP_ATOMIC | GFP_KERNEL is meaningless and won't work.  Actually it never
worked, even in 2.4.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-22 22:17:37 -07:00
Paolo 'Blaisorblade' Giarrusso fea03cb40a [PATCH] uml: avoid fixing faults while atomic
Following i386, we should maybe refuse trying to fault in pages when we're
doing atomic operations, because to handle the fault we could need to take
already taken spinlocks.

Also, if we're doing an atomic operation (in the sense of in_atomic()) we're
surely in kernel mode and we're surely going to handle adequately the failed
fault, so it's safe to behave this way.

Currently, on UML SMP is rarely used, and we don't support PREEMPT, so this is
unlikely to create problems right now, but it might in the future.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-22 22:17:36 -07:00
Paolo 'Blaisorblade' Giarrusso 12ebcd73e4 [PATCH] uml: run mconsole "sysrq" in process context
Things are breaking horribly with sysrq called in interrupt context.  I want
to try to fix it, but probably this is simpler.  To tell the truth, sysrq is
normally run in interrupt context, so there shouldn't be any problem.

There's also a warning from the fault handler because it's run in atomic
context (I have a patch for that, only I deferred it).  This is why I'm doing
this.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-22 22:17:36 -07:00
Paolo 'Blaisorblade' Giarrusso dc36abf34e [PATCH] uml: fix condition in tlb flush
Avoid setting w = 0 twice.  Spotted this (trivial) thing which is needed for
another patch.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-22 22:17:36 -07:00
Paolo 'Blaisorblade' Giarrusso 546fe1cbf9 [PATCH] uml: fix hang in TT mode on fault
The current code doesn't handle well general protection faults on the host -
it thinks that cr2 is always the address of a page fault.  While actually, on
general protection faults, that address is not accessible, so we'd better
assume we couldn't satisfy the fault.  Currently instead we think we've fixed
it, so we go back, retry the instruction and fault again endlessly.

This leads to the kernel hanging when doing copy_from_user(dest, -1, ...) in
TT mode, since reading *(-1) causes a GFP, and we don't support kernel
preemption.

Thanks to Luo Xin for testing UML with LTP and reporting the failures he got.

Cc: Luo Xin <luothing@sina.com>
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-22 22:17:36 -07:00
Paolo 'Blaisorblade' Giarrusso a8bfb94c58 [PATCH] strlcat: use for uml umid.c
Simplify the code by using strlcat() instead of strncat() and manual
appending.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-22 22:17:36 -07:00
Paolo 'Blaisorblade' Giarrusso 3a02d6c051 [PATCH] uml: don't remove umid files in conflict case
Only remove the UML pidfile and management socket if we created them.
Currently in case two UMLs are started with the same umid, the second will
remove the first's ones.

Probably we should also panic() at that point, not sure however.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-22 22:17:36 -07:00
Paolo 'Blaisorblade' Giarrusso efb0372bba [PATCH] uml: fix compile warning after consolidation patch
The header declaring this function wasn't included, so the function declaration
was totally bogus wrt. the proto - even if this wasn't going to fail at all.

It was so bad that the compile warning I got was "control reaches end of
non-void function", i.e. missing return. Actually, this has been there for ages,
the consolidation patch just added the warning which was needed to clean it up.
Nice. Really.

Cc: Allan Graves <allan.graves@gmail.com>
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-21 16:16:30 -07:00
Paolo 'Blaisorblade' Giarrusso a46c904764 [PATCH] uml: comment about cast build fix
Explain why the casting we do to silence this warning is indeed safe.

It is because the field we're casting from, though being 64-bit wide, was filled
with a pointer in first place by ourselves.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-21 16:16:30 -07:00
Paolo 'Blaisorblade' Giarrusso ae756df8dd [PATCH] uml: readd removed unistd.h inclusion
Readd this header (deleted in 60d339f6fe). A
warning is spit out here about undeclared getpgrp().

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-21 16:16:30 -07:00
Paolo 'Blaisorblade' Giarrusso 41c79dc382 [PATCH] uml: fix bogus HOST_ELF_CLASS symbol name
Even if with a bit of misunderstanding, Al fixed this in commit
95608261da.

Well, the symbol was intended to come from userspace (it exists there on normal
host), but since some hosts may miss that, using the kernel one is just as fine.
However, rename it to be named consistently with the rest.

Actually, he missed converting ELFCLASS32 to coming from kernel headers. For
consistence, add ELFCLASS64 too.

Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-21 16:16:30 -07:00
Paolo 'Blaisorblade' Giarrusso fd74810478 [PATCH] uml: Fix conflict between libc and ipv6
gcc is now complaining during link on some hosts - fix it as for other things.
Reported by Antoine Martin <antoine@nagafix.co.uk>.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-21 16:16:30 -07:00
Paolo 'Blaisorblade' Giarrusso 8e5cb35a60 [PATCH] uml: fix uname output on 32-bit binary on 64-bit host
Translate uname output taken from the host if needed.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-21 16:16:30 -07:00
Paolo 'Blaisorblade' Giarrusso 36decba90b [PATCH] uml: fix modify_ldt - missing break in switch
I am a lamer :-(. Luckily, Luo Xin performed LTP testing and found this failure.
Btw, the fact that the patch in which I introduced this was merged shows that:

a) I'm really trusted by people
b) sometimes they're wrong about point a).
c) lack of time for reviewers.

CC: Luo Xin <luothing@sina.com>
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-21 16:16:29 -07:00
Paolo 'Blaisorblade' Giarrusso 76629ac154 [PATCH] uml: remove verify_area_{tt,skas}
When removing verify_area, verify_area_{tt,skas} were forgotten.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-21 16:16:29 -07:00
Jeff Dike 3013449243 [PATCH] uml: UML/i386 cmpxchg fix
Using native cmpxchg offers a slight performance improvement in uml/i386.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-17 11:50:01 -07:00
Jeff Dike 1f87b1e6e6 [PATCH] uml: remove include of asm/elf.h
asm/elf.h is bad on x86_64, and i386 doesn't need it any more after Al's
cleanup.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-17 11:50:00 -07:00
Jeff Dike 2867ace675 [PATCH] uml: return a real error code
do_aio used to return -1 on error instead of errno.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-17 11:50:00 -07:00
Jeff Dike 114069f738 [PATCH] uml: merge mem_user.c and mem.c
The serial UML OS-abstraction layer patch (um/kernel dir).

This joins mem_user.c and mem.c files.

Signed-off-by: Gennady Sharapov <Gennady.V.Sharapov@intel.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-17 11:50:00 -07:00
Jeff Dike 0f80bc85c5 [PATCH] uml: move libc code out of mem_user.c and tempfile.c
The serial UML OS-abstraction layer patch (um/kernel dir).

This moves all system calls from mem_user.c and tempfile.c files under
os-Linux dir.

Signed-off-by: Gennady Sharapov <Gennady.V.Sharapov@intel.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-17 11:50:00 -07:00
Jeff Dike b4fd310e16 [PATCH] uml: preserve errno in error paths
The poster child for this patch is the third tuntap_user hunk.  When an ioctl
fails, it properly closes the opened file descriptor and returns.  However,
the close resets errno to 0, and the 'return errno' that follows returns 0
rather than the value that ioctl set.  This caused the caller to believe that
the device open succeeded and had opened file descriptor 0, which caused no
end of interesting behavior.

The rest of this patch is a pass through the UML sources looking for places
where errno could be reset before being passed back out.  A common culprit is
printk, which could call write, being called before errno is returned.

In some cases, where the code ends up being much smaller, I just deleted the
printk.

There was another case where a caller of run_helper looked at errno after a
failure, rather than the return value of run_helper, which was the errno value
that it wanted.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-17 11:50:00 -07:00
Jeff Dike 64b7673f91 [PATCH] uml: Remove some build warnings
These ugly double-casts are the result of gdb complaining about size

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-17 11:50:00 -07:00
Jeff Dike d9f0d91510 [PATCH] uml: Remove a useless include
linux/inet.h isn't needed, and on my system, is empty.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-17 11:50:00 -07:00
Jeff Dike edcc2205d3 [PATCH] uml: Remove an unused file
This removes a file which is no longer used.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-17 11:49:59 -07:00
Jeff Dike 3eddddcf23 [PATCH] uml: breakpoint an arbitrary thread
This patch implements a stack trace for a thread, not unlike sysrq-t does.
The advantage to this is that a break point can be placed on showreqs, so that
upon showing the stack, you jump immediately into the debugger.  While sysrq-t
does the same thing, sysrq-t shows *all* threads stacks.  It also doesn't work
right now.  In the future, I thought it might be acceptable to make this show
all pids stacks, but perhaps leaving well enough alone and just using sysrq-t
would be okay.  For now, upon receiving the stack command, UML switches
context to that thread, dumps its registers, and then switches context back to
the original thread.  Since UML compacts all threads into one of 4 host
threads, this sort of mechanism could be expanded in the future to include
other debugging helpers that sysrq does not cover.

Note by jdike - The main benefit to this is that it brings an arbitrary thread
back into context, where it can be examined by gdb.  The fact that it dumps it
stack is secondary.  This provides the capability to examine a sleeping
thread, which has existed in tt mode, but not in skas mode until now.

Also, the other threads, that sysrq doesn't cover, can be gdb-ed directly
anyway.

Signed-off-by: Allan Graves<allan.graves@gmail.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-17 11:49:59 -07:00
Jeff Dike f6e34c6af6 [PATCH] uml: _switch_to code consolidation
This patch moves code that is in both switch_to_tt and switch_to_skas to the
top level _switch_to function, keeping us from duplicating code.  It is
required for the stack trace patch to work properly.

Signed-off-by: Allan Graves <allan.graves@gmail.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-17 11:49:59 -07:00
Sam Ravnborg 5bb7826900 kbuild: rename prepare to archprepare to fix dependency chain
When introducing the generic asm-offsets.h support the dependency
chain for the prepare targets was changed. All build scripts expecting
include/asm/asm-offsets.h to be made when using the prepare target would broke.
With the limited number of prepare targets left in arch Makefiles
the trivial solution was to introduce a new arch specific target: archprepare

The dependency chain looks like this now:

prepare
  |
  +--> prepare0
         |
         +--> archprepare
                |
		+--> scripts_basic
                +--> prepare1
                       |
                       +---> prepare2
                               |
                               +--> prepare3

So prepare 3 is processed before prepare2 etc.
This guaantees that the asm symlink, version.h, scripts_basic
are all updated before archprepare is processed.

prepare0 which build the asm-offsets.h file will need the
actions performed by archprepare.

The head target is now named prepare, because users scripts will most
likely use that target, but prepare-all has been kept for compatibility.
Updated Documentation/kbuild/makefiles.txt.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2005-09-11 22:30:22 +02:00
Paolo 'Blaisorblade' Giarrusso 16b036786a [PATCH] uml: avoid already done dirtying
The PTE returned from handle_mm_fault is already marked as dirty and accessed
if needed.

Also, since this is not set with set_pte() (which sets NEWPAGE and NEWPROT as
needed), this wouldn't work anyway.

This version has been updated and fixed, thanks to some feedback from Jeff Dike.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-10 12:00:18 -07:00
Paolo 'Blaisorblade' Giarrusso d129f31236 [PATCH] uml: fix fault handler on write
The UML fault handler was recently changed to enforce PROT_NONE protections,
by requiring VM_READ or VM_EXEC on VMA's.

However, by mistake, things were changed such that VM_READ is always checked,
also on write faults; so a VMA mapped with only PROT_WRITE is not readable
(unless it's prefaulted with MAP_POPULATE or with a write), which is different
from i386.

Discovered while testing remap_file_pages protection support.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-10 12:00:18 -07:00
Paolo 'Blaisorblade' Giarrusso d99c4022f6 [PATCH] uml: inline mk_pte and various friends
Turns out that, for UML, a *lot* of VM-related trivial functions are not
inlined but rather normal functions.

In other sections of UML code, this is justified by having files which
interact with the host and cannot therefore include kernel headers, but in
this case there's no such justification.

I've had to turn many of them to macros because of missing declarations. While
doing this, I've decided to reuse some already existing macros.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-10 12:00:18 -07:00
Paolo 'Blaisorblade' Giarrusso a7d0c21033 [PATCH] i386 / uml: add dwarf sections to static link script
Inside the linker script, insert the code for DWARF debug info sections. This
may help GDB'ing a Uml binary. Actually, it seems that ld is able to guess
what I added correctly, but normal linker scripts include this section so it
should be correct anyway adding it.

On request by Sam Ravnborg <sam@ravnborg.org>, I've added it to
asm-generic/vmlinux.lds.s. I've also moved there the stabs debug section,
used the new macro in i386 linker script and added DWARF debug section to
that.

In the truth, I've not been able to verify the difference in GDB behaviour
after this change (I've seen large improvements with another patch). This
may depend on my binutils version, older one may have worse defaults.

However, this section is present in normal linker script, so add it at
least for the sake of cleanness.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-10 12:00:17 -07:00
Paolo 'Blaisorblade' Giarrusso 2d5cbf324c [PATCH] Uml: more cleaning
We must remove even arch/um/os-Linux/util/mk_user_constants, which we don't do.
Also, Kconfig_arch must be listed only once, between CLEAN_FILES.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-10 12:00:17 -07:00
Linus Torvalds 486a153f0e Merge master.kernel.org:/pub/scm/linux/kernel/git/sam/kbuild 2005-09-09 15:46:49 -07:00
Sam Ravnborg f64a227b6b kbuild: um fix so it compile with generic asm-offsets.h support
um has it own set of files for asm-offsets. So for now the
gen-asm-offset macro is just duplicated in the um Makefile.

This may well be the final solution since um is a bit special compared
to other architectures - time will tell.

Also added a dummy arch/um/kernel/asm-offsets.h file to keep kbuild happy.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2005-09-09 23:10:54 +02:00