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* sh: Mass ctrl_in/outX to __raw_read/writeX conversion.Paul Mundt2010-01-261-3/+3
| | | | | | | | | | | The old ctrl in/out routines are non-portable and unsuitable for cross-platform use. While drivers/sh has already been sanitized, there is still quite a lot of code that is not. This converts the arch/sh/ bits over, which permits us to flag the routines as deprecated whilst still building with -Werror for the architecture code, and to ensure that future users are not added. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* sh: Move over to dynamically allocated FPU context.Paul Mundt2010-01-131-2/+2
| | | | | | | | | | | | | | | | | | | | | This follows the x86 xstate changes and implements a task_xstate slab cache that is dynamically sized to match one of hard FP/soft FP/FPU-less. This also tidies up and consolidates some of the SH-2A/SH-4 FPU fragmentation. Now fpu state restorers are commonly defined, with the init_fpu()/fpu_init() mess reworked to follow the x86 convention. The fpu_init() register initialization has been replaced by xstate setup followed by writing out to hardware via the standard restore path. As init_fpu() now performs a slab allocation a secondary lighterweight restorer is also introduced for the context switch. In the future the DSP state will be rolled in here, too. More work remains for math emulation and the SH-5 FPU, which presently uses its own special (UP-only) interfaces. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* sh: TS_RESTORE_SIGMASK conversion.Paul Mundt2009-10-141-10/+14
| | | | | | | | | | | Replace TIF_RESTORE_SIGMASK with TS_RESTORE_SIGMASK and define our own set_restore_sigmask() function. This saves the costly SMP-safe set_bit operation, which we do not need for the sigmask flag since TIF_SIGPENDING always has to be set too. Based on the x86 and powerpc change. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* sh: Optimize the setup_rt_frame() I-cache flush.Paul Mundt2009-10-141-2/+1
| | | | | | | | This only needs to flush the return code via the legacy path, and just invalidates uselessly otherwise. This makes the behaviour consistent for all of the trampoline setup paths. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* sh: Use boot_cpu_data for FPU tests in sigcontext paths.Paul Mundt2009-10-141-3/+3
| | | | | | | We do not want to use smp_processor_id() from these paths, as they trip preempt BUGs. Switch the test over to the boot cpu directly. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* Merge branch 'master' of ↵Paul Mundt2009-09-161-0/+2
|\ | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 Conflicts: arch/sh/kernel/vmlinux.lds.S
| * KEYS: Add a keyctl to install a process's session keyring on its parent [try #6]David Howells2009-09-021-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a keyctl to install a process's session keyring onto its parent. This replaces the parent's session keyring. Because the COW credential code does not permit one process to change another process's credentials directly, the change is deferred until userspace next starts executing again. Normally this will be after a wait*() syscall. To support this, three new security hooks have been provided: cred_alloc_blank() to allocate unset security creds, cred_transfer() to fill in the blank security creds and key_session_to_parent() - which asks the LSM if the process may replace its parent's session keyring. The replacement may only happen if the process has the same ownership details as its parent, and the process has LINK permission on the session keyring, and the session keyring is owned by the process, and the LSM permits it. Note that this requires alteration to each architecture's notify_resume path. This has been done for all arches barring blackfin, m68k* and xtensa, all of which need assembly alteration to support TIF_NOTIFY_RESUME. This allows the replacement to be performed at the point the parent process resumes userspace execution. This allows the userspace AFS pioctl emulation to fully emulate newpag() and the VIOCSETTOK and VIOCSETTOK2 pioctls, all of which require the ability to alter the parent process's PAG membership. However, since kAFS doesn't use PAGs per se, but rather dumps the keys into the session keyring, the session keyring of the parent must be replaced if, for example, VIOCSETTOK is passed the newpag flag. This can be tested with the following program: #include <stdio.h> #include <stdlib.h> #include <keyutils.h> #define KEYCTL_SESSION_TO_PARENT 18 #define OSERROR(X, S) do { if ((long)(X) == -1) { perror(S); exit(1); } } while(0) int main(int argc, char **argv) { key_serial_t keyring, key; long ret; keyring = keyctl_join_session_keyring(argv[1]); OSERROR(keyring, "keyctl_join_session_keyring"); key = add_key("user", "a", "b", 1, keyring); OSERROR(key, "add_key"); ret = keyctl(KEYCTL_SESSION_TO_PARENT); OSERROR(ret, "KEYCTL_SESSION_TO_PARENT"); return 0; } Compiled and linked with -lkeyutils, you should see something like: [dhowells@andromeda ~]$ keyctl show Session Keyring -3 --alswrv 4043 4043 keyring: _ses 355907932 --alswrv 4043 -1 \_ keyring: _uid.4043 [dhowells@andromeda ~]$ /tmp/newpag [dhowells@andromeda ~]$ keyctl show Session Keyring -3 --alswrv 4043 4043 keyring: _ses 1055658746 --alswrv 4043 4043 \_ user: a [dhowells@andromeda ~]$ /tmp/newpag hello [dhowells@andromeda ~]$ keyctl show Session Keyring -3 --alswrv 4043 4043 keyring: hello 340417692 --alswrv 4043 4043 \_ user: a Where the test program creates a new session keyring, sticks a user key named 'a' into it and then installs it on its parent. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* | sh: Improve unwind info for signalsCarl Shaw2009-08-241-1/+11
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | GCC does not issue unwind information for function epilogues. Unfortunately we can catch a signal during an epilogue. The signal handler writes the current context and signal return code onto the stack overwriting previous contents. During unwinding, libgcc can try to restore registers from the stack and restores corrupted ones. This can lead to segmentation, misaligned access and sigbus faults. For example, consider the following code: mov.l r12,@-r15 mov.l r14,@-r15 sts.l pr,@-r15 mov r15,r14 <do stuff> mov r14, r15 lds.l @r15+, pr <<< SIGNAL HERE mov.l @r15+, r14 mov.l @r15+, r12 rts Unwind is aware that pr was pushed to stack in prolog, so tries to restore it. Unfortunately it restores the last word of the signal handler code placed on the stack by the kernel. This patch tries to avoid the problem by adding a guard region on the stack between where the function pushes data and where the signal handler pushes its return code. We probably don't see this problem often because exception handling unwinding in an epilogue only occurs due to a pthread cancel signal. Also the kernel signal stack handler alignment of 8 bytes could hide the occurance of this problem sometimes as the stack may not be trampled at a particular required word. This is not guaranteed to always work. It relies on a frame pointer existing for the function (so it can get the correct sp value) which is not always the case for the SH4. Modifications will also be made to libgcc for the case where there is no fp. Signed-off-by: Carl Shaw <carl.shaw@st.com> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* sh: Fix declaration of __kernel_sigreturn and __kernel_rt_sigreturnMatt Fleming2009-06-181-2/+2
| | | | | | | | | | | | | | | | | GCC 4.5.0 complains about the declaration of variables __kernel_sigreturn and __kernel_rt_sigreturn because they have type void. Correctly declare these symbols as functions to fix the following error, arch/sh/kernel/signal_32.c: In function 'setup_frame': arch/sh/kernel/signal_32.c:368:14: error: taking address of expression of type 'void' arch/sh/kernel/signal_32.c: In function 'setup_rt_frame': arch/sh/kernel/signal_32.c:452:14: error: taking address of expression of type 'void' make[1]: *** [arch/sh/kernel/signal_32.o] Error 1 make: *** [arch/sh/kernel] Error 2 Signed-off-by: Matt Fleming <matt@console-pimps.org> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* sh: Fix up spurious syscall restarting.Paul Mundt2009-01-291-3/+1
| | | | | | | | | The T-bit manipulation for syscall error checking had the side effect of spuriously returning ERESTART* errno values over EINTR. So, we simplify the error checking a bit and leave the T-bit alone. Reported-by: Kaz Kojima <kkojima@rr.iij4u.or.jp> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* sh: Provide asm/syscall.h for SH-5.Paul Mundt2008-12-221-1/+0
| | | | | | This provides the asm/syscall.h implementation for sh64 parts. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* sh: Force pending restarted system calls to return -EINTR.Paul Mundt2008-09-241-0/+6
| | | | Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* sh: Flag T-bit for syscall restart.Paul Mundt2008-09-121-22/+31
| | | | Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* sh: fixup many sparse errors.Paul Mundt2008-09-081-6/+4
| | | | Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* sh: Make syscall tracer use tracehook notifiers, add TIF_NOTIFY_RESUME.Paul Mundt2008-08-021-7/+15
| | | | | | | | | | | | | | This follows the changes in commits: 7d6d637dac2050f30a1b57b0a3dc5de4a10616ba 4f72c4279eab1e5f3ed1ac4e55d4527617582392 on powerpc. Adding in TIF_NOTIFY_RESUME, and cleaning up the syscall tracing to be more generic. This is an incremental step to turning on tracehook, as well as unifying more of the ptrace and signal code across the 32/64 split. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* sh: Conditionally re-enable IRQs in fault path.Stuart Menefy2008-07-281-2/+1
| | | | | | | | | | | | | The current kernel behaviour is to reenable interrupts unconditionally when taking a page fault. This patch changes this to only enable them if interrupts were previously enabled. It also fixes a problem seen with this fix in place: the kernel previously flushed the vsyscall page when handling a signal, which is not only unncessary, but caused a possible sleep with interrupts disabled. Signed-off-by: Stuart Menefy <stuart.menefy@st.com> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* sh: Optimized flush_icache_range() implementation.Chris Smith2008-07-281-8/+2
| | | | | | | | | Add implementation of flush_icache_range() suitable for signal handler and kprobes. Remove flush_cache_sigtramp() and change signal.c to use flush_icache_range(). Signed-off-by: Chris Smith <chris.smith@st.com> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* sh: Initial ELF FDPIC support.Paul Mundt2008-07-281-2/+23
| | | | | | | | | This adds initial support for ELF FDPIC on MMU-less SH, as per version 0.2 of the ABI definition at: http://www.codesourcery.com/public/docs/sh-fdpic/sh-fdpic-abi.txt Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* sh: Fix occasional FPU register corruption under preempt.Paul Mundt2008-03-261-0/+1
| | | | | | | | | | | Presently with preempt enabled there's the possibility to be preempted after the TIF_USEDFPU test and the register save, leading to bogus state post-__switch_to(). Use an explicit preempt_disable()/enable() pair around unlazy_fpu()/clear_fpu() to avoid this. Follows the x86 change. Reported-by: Takuo Koguchi <takuo.koguchi.sw@hitachi.com> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* sh: GUSA atomic rollback support.Stuart Menefy2008-01-281-18/+0
| | | | | | | | | | This implements kernel-level atomic rollback built on top of gUSA, as an alternative non-IRQ based atomicity method. This is generally a faster method for platforms that are lacking the LL/SC pairs that SH-4A and later use, and is only supportable on legacy cores. Signed-off-by: Stuart Menefy <stuart.menefy@st.com> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* sh: Move in the SH-5 signal trampoline impl.Paul Mundt2008-01-281-0/+629
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
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