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2012-04-10powerpc: Fix page fault with lockdep regressionBenjamin Herrenschmidt1-18/+21
commit a546498f3bf9aac311c66f965186373aee2ca0b0 introduced a regression on 32-bit when irq tracing is enabled by exposing an old bug in our irq tracing code for exception entry. The code would save and restore some GPRs around the calls to the C lockdep code, however, it tries to be too smart for its own good and restores some of the GPRs from the exception frame (as saved there on exception entry). However, for page faults, we do replace those GPRs with arguments to do_page_fault before we call transfer_to_handler and so restoring from the exception frame is plain wrong in this case. This was fine as long as we didn't touch the interrupt state when taking page fault, but when I started doing it, it would trigger the lockdep calls and the bug. This fixes it by cleaning up that code a bit. It did create a small stack frame for the sake of backtraces, so let's make it a bit bigger and use it to save and restore the stuff we care about. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-22powerpc: Fix various issues with return to userspaceBenjamin Herrenschmidt1-1/+1
We have a few problems when returning to userspace. This is a quick set of fixes for 3.3, I'll look into a more comprehensive rework for 3.4. This fixes: - We kept interrupts soft-disabled when schedule'ing or calling do_signal when returning to userspace as a result of a hardware interrupt. - Rename do_signal to do_notify_resume like all other archs (and do_signal_pending back to do_signal, which it was before Roland changed it). - Add the missing call to key_replace_session_keyring() to do_notify_resume(). Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> ---
2011-11-16powerpc/trace: Add a dummy stack frame for trace_hardirqs_offKevin Hao1-0/+15
The trace_hardirqs_off will use CALLER_ADDR0 and CALLER_ADDR1. If an exception occurs in user mode, there is only one stack frame on the stack and accessing the CALLER_ADDR1 will causes the following call trace. So we create a dummy stack frame to make trace_hardirqs_off happy. WARNING: at kernel/smp.c:459 Modules linked in: NIP: c0093280 LR: c00930a0 CTR: c0010780 REGS: edb87ae0 TRAP: 0700 Not tainted (3.1.0) MSR: 00021002 <ME,CE> CR: 28002888 XER: 00000000 TASK = edce2ac0[17658] 'mthread-lock-on' THREAD: edb86000 CPU: 5 GPR00: 00000001 edb87b90 edce2ac0 00000005 c0019594 edb87bd8 00000001 00000fe3 GPR08: 00041000 c084138c 4e20120d edb87b90 48002888 1001aa7c 00000000 00000000 GPR16: 48830000 10012a8c 00000000 10000af4 00000001 c0810000 00000000 00000000 GPR24: ee9aa920 c0816a18 00000000 00000005 c0019594 edb87bd8 ee20178c edb87b90 NIP [c0093280] smp_call_function_many+0x214/0x2b4 LR [c00930a0] smp_call_function_many+0x34/0x2b4 Call Trace: [edb87b90] [c00930a0] smp_call_function_many+0x34/0x2b4 (unreliable) [edb87bd0] [c00194ec] __flush_tlb_page+0xac/0x100 [edb87c00] [c001957c] flush_tlb_page+0x3c/0x54 [edb87c10] [c00180ac] ptep_set_access_flags+0x74/0x12c [edb87c40] [c0128068] handle_pte_fault+0x2f0/0x9ac [edb87cb0] [c0128c3c] handle_mm_fault+0x104/0x1dc [edb87ce0] [c05f40f4] do_page_fault+0x2dc/0x630 [edb87e50] [c001078c] handle_page_fault+0xc/0x80 Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-01-21powerpc/ppc32/tracing: Add stack frame to calls of trace_hardirqs_on/offSteven Rostedt1-0/+11
32-bit variant of the previous patch for 64-bit: << When an interrupt occurs in userspace, we can call trace_hardirqs_on/off() With one level stack. But if we have irqsoff tracing enabled, it checks both CALLER_ADDR0 and CALLER_ADDR1. The second call goes two stack frames up. If this is from user space, then there may not exist a second stack.... >> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-11-29powerpc: Remove second definition of STACK_FRAME_OVERHEADStephen Rothwell1-0/+1
Since STACK_FRAME_OVERHEAD is defined in asm/ptrace.h and that is ASSEMBER safe, we can just include that instead of going via asm-offsets.h. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-05-05powerpc/47x: Base ppc476 supportDave Kleikamp1-0/+5
This patch adds the base support for the 476 processor. The code was primarily written by Ben Herrenschmidt and Torez Smith, but I've been maintaining it for a while. The goal is to have a single binary that will run on 44x and 47x, but we still have some details to work out. The biggest is that the L1 cache line size differs on the two platforms, but it's currently a compile-time option. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Torez Smith <lnxtorez@linux.vnet.ibm.com> Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com> Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2009-08-20powerpc: Use names rather than numbers for SPRGs (v2)Benjamin Herrenschmidt1-10/+10
The kernel uses SPRG registers for various purposes, typically in low level assembly code as scratch registers or to hold per-cpu global infos such as the PACA or the current thread_info pointer. We want to be able to easily shuffle the usage of those registers as some implementations have specific constraints realted to some of them, for example, some have userspace readable aliases, etc.. and the current choice isn't always the best. This patch should not change any code generation, and replaces the usage of SPRN_SPRGn everywhere in the kernel with a named replacement and adds documentation next to the definition of the names as to what those are used for on each processor family. The only parts that still use the original numbers are bits of KVM or suspend/resume code that just blindly needs to save/restore all the SPRGs. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-06-26powerpc: Add irqtrace support for 32-bit powerpcBenjamin Herrenschmidt1-4/+123
Based on initial work from: Dale Farnsworth <dale@farnsworth.org> Add the low level irq tracing hooks for 32-bit powerpc needed to enable full lockdep functionality. The approach taken to deal with the code in entry_32.S is that we don't trace all the transitions of MSR:EE when we just turn it off to peek at TI_FLAGS without races. Only when we are calling into C code or returning from exceptions with a state that have changed from what lockdep thinks. There's a little bugger though: If we take an exception that keeps interrupts enabled (such as an alignment exception) while interrupts are enabled, we will call trace_hardirqs_on() on the way back spurriously. Not a big deal, but to get rid of it would require remembering in pt_regs that the exception was one of the type that kept interrupts enabled which we don't know at this stage. (Well, we could test all cases for regs->trap but that sucks too much). Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Tested-by: Kumar Gala <galak@kernel.crashing.org>
2009-02-23powerpc: Unify opcode definitions and supportKumar Gala1-4/+4
Create a new header that becomes a single location for defining PowerPC opcodes used by code that is either generationg instructions at runtime (fixups, debug, etc.), emulating instructions, or just compiling instructions old assemblers don't know about. We currently don't handle the floating point emulation or alignment decode as both are better handled by the specific decode support they already have. Added support for the new dcbzl, dcbal, msgsnd, tlbilx, & wait instructions since older assemblers don't know about them. Signed-off-by: Kumar Gala <galak@kernel.crashing.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-02-23powerpc32, ftrace: dynamic function graph tracerSteven Rostedt1-2/+6
This patch gets function graph tracing working with dynamic function tracer on PowerPC32. Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-02-23powerpc32, ftrace: port function graph tracer to ppc32, static onlySteven Rostedt1-1/+42
This patch ports the function graph tracer for PowerPC, but only for static function tracing. Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-02-23powerpc32, ftrace: save and restore mcount regs with macroSteven Rostedt1-59/+9
Impact: clean up Use a macro to save and restore the registers for PowerPC32, since that code is duplicated. This is similar to the work done by Cyrill Gorcunov for the mcount code in x86_64. Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-02-12powerpc/book-3e: Introduce concept of Book-3e MMUKumar Gala1-3/+3
The Power ISA 2.06 spec introduces a standard MMU programming model that is based on the Freescale Book-E MMU programing model. The Freescale version is pretty backwards compatiable with the ISA 2.06 definition so we are starting to refactor some of the Freescale code so it can be easily shared. Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-11-28powerpc: ftrace, do nothing in mcount call for dyn ftraceSteven Rostedt1-31/+9
Impact: quicken mcount calls that are not replaced by dyn ftrace Dynamic ftrace no longer does on the fly recording of mcount locations. The mcount locations are now found at compile time. The mcount function no longer needs to store registers and call a stub function. It can now just simply return. Since there are some functions that do not get converted to a nop (.init sections and other code that may disappear), this patch should help speed up that code. Also, the stub for mcount on PowerPC 32 can not be a simple branch link register like it is on PowerPC 64. According to the ABI specification: "The _mcount routine is required to restore the link register from the stack so that the profiling code can be inserted transparently, whether or not the profiled function saves the link register itself." This means that we must restore the link register that was used to make the call to mcount. The minimal mcount function for PPC32 ends up being: mcount: mflr r0 mtctr r0 lwz r0, 4(r1) mtlr r0 bctr Where we move the link register used to call mcount into the ctr register, and then restore the link register from the stack. Then we use the ctr register to jump back to the mcount caller. The r0 register is free for us to use. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-20ftrace: rename FTRACE to FUNCTION_TRACERSteven Rostedt1-1/+1
Due to confusion between the ftrace infrastructure and the gcc profiling tracer "ftrace", this patch renames the config options from FTRACE to FUNCTION_TRACER. The other two names that are offspring from FTRACE DYNAMIC_FTRACE and FTRACE_MCOUNT_RECORD will stay the same. This patch was generated mostly by script, and partially by hand. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-28powerpc: Add TIF_NOTIFY_RESUME support for tracehookRoland McGrath1-2/+2
This adds TIF_NOTIFY_RESUME support for powerpc. When set, we call tracehook_notify_resume() on the way to user mode. This overloads do_signal() to do the work, but changes its arguments to it has the TIF_* bits handy in a register and drops the useless first argument that was always zero. Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-28powerpc: Make syscall tracing use tracehook.h helpersRoland McGrath1-1/+6
This changes powerpc syscall tracing to use the new tracehook.h entry points. There is no change, only cleanup. In addition, the assembly changes allow do_syscall_trace_enter() to abort the syscall without losing the information about the original r0 value. Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-28powerpc/booke: Clean up the hardware watchpoint supportKumar Gala1-3/+3
* CONFIG_BOOKE is selected by CONFIG_44x so we dont need both * Fixed a few comments * Go back to only using DBCR0_IDM to determine if we are using debug resources. Signed-off-by: Kumar Gala <galak@kernel.crashing.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-25powerpc: BookE hardware watchpoint supportLuis Machado1-3/+3
This patch implements support for HW based watchpoint via the DBSR_DAC (Data Address Compare) facility of the BookE processors. It does so by interfacing with the existing DABR breakpoint code and adding the necessary bits and pieces for the new bits to be properly set or cleared Signed-off-by: Luis Machado <luisgpm@br.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-15Merge commit '85082fd7cbe3173198aac0eb5e85ab1edcc6352c' into test-buildBenjamin Herrenschmidt1-0/+127
Manual fixup of: arch/powerpc/Kconfig
2008-06-26powerpc/85xx: add DOZE/NAP support for e500 coreKumar Gala1-4/+4
The e500 core enter DOZE/NAP power-saving modes when the core go to cpu_idle routine. The power management default running mode is DOZE, If the user echo 1 > /proc/sys/kernel/powersave-nap the system will change to NAP running mode. Signed-off-by: Dave Liu <daveliu@freescale.com> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-06-23ftrace: store mcount address in rec->ipAbhishek Sagar1-0/+4
Record the address of the mcount call-site. Currently all archs except sparc64 record the address of the instruction following the mcount call-site. Some general cleanups are entailed. Storing mcount addresses in rec->ip enables looking them up in the kprobe hash table later on to check if they're kprobe'd. Signed-off-by: Abhishek Sagar <sagar.abhishek@gmail.com> Cc: davem@davemloft.net Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-02[POWERPC] 40x/Book-E: Save/restore volatile exception registersKumar Gala1-2/+123
On machines with more than one exception level any system register that might be modified by the "normal" exception level needs to be saved and restored on taking a higher level exception. We already are saving and restoring ESR and DEAR. For critical level add SRR0/1. For debug level add CSRR0/1 and SRR0/1. For machine check level add DSRR0/1, CSRR0/1, and SRR0/1. On FSL Book-E parts we always save/restore the MAS registers for critical, debug, and machine check level exceptions. On 44x we always save/restore the MMUCR. Additionally, we save and restore the ksp_limit since we have to adjust it for each exception level. Signed-off-by: Kumar Gala <galak@kernel.crashing.org> Acked-by: Paul Mackerras <paulus@samba.org>
2008-06-02[POWERPC] Rework EXC_LEVEL_EXCEPTION_PROLOG codeKumar Gala1-13/+0
* Cleanup the code a bit my allocating an INT_FRAME on our exception stack there by make references go from GPR11-INT_FRAME_SIZE(r8) to just GPR11(r8) * simplify {lvl}_transfer_to_handler code by moving the copying of the temp registers we use if we come from user space into the PROLOG * If the exception came from kernel mode copy thread_info flags, preempt, and task pointer from the process thread_info. Signed-off-by: Kumar Gala <galak@kernel.crashing.org> Acked-by: Paul Mackerras <paulus@samba.org>
2008-05-26ftrace: powerpc clean upsSteven Rostedt1-9/+2
This patch cleans up the ftrace code in PowerPC based on the comments from Michael Ellerman. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: proski@gnu.org Cc: a.p.zijlstra@chello.nl Cc: Pekka Paalanen <pq@iki.fi> Cc: Steven Rostedt <srostedt@redhat.com> Cc: linuxppc-dev@ozlabs.org Cc: Soeren Sandmann Pedersen <sandmann@redhat.com> Cc: paulus@samba.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-23ftrace: support for PowerPCSteven Rostedt1-0/+130
This patch adds full support for ftrace for PowerPC (both 64 and 32 bit). This includes dynamic tracing and function filtering. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-16[POWERPC] Defer processing of interrupts when the CPU wakes from sleep modePaul Mackerras1-0/+8
This provides a way to defer processing of an interrupt that wakes the processor out of sleep mode. On 32-bit platforms that use an interrupt to wake the processor, we have to have interrupts enabled in hardware at the point where we go to sleep, otherwise the processor will never wake up. However, because interrupts are logically disabled at this point, we don't want to process the interrupt straight away. This is handled by setting the _TLF_SLEEPING flag. When we get an interrupt and _TLF_SLEEPING is set, we firstly clear the MSR_EE (external interrupt enable) bit in the saved MSR value, and secondly we then return to the address in the link register, like we do for _TLF_NAPPING, but without actually handling the interrupt. Note that this is handled somewhat differently on powerbooks, so this new code will only be used on non-Apple machines. Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-05-14[POWERPC] Define and use TLF_RESTORE_SIGMASKRoland McGrath1-2/+2
Replace TIF_RESTORE_SIGMASK with TLF_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. Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-29[POWERPC] Add IRQSTACKS support on ppc32Kumar Gala1-2/+3
This makes it possible to use separate stacks for hard and soft IRQs on 32-bit powerpc as well as on 64-bit. The code for 32-bit is just the 32-bit analog of the 64-bit code. * Added allocation and initialization of the irq stacks. We limit the stacks to be in lowmem for ppc32. * Implemented ppc32 versions of call_do_softirq() and call_handle_irq() to switch the stack pointers * Reworked how we do stack overflow detection. We now keep around the limit of the stack in the thread_struct and compare against the limit to see if we've overflowed. We can now use this on ppc64 if desired. [ paulus@samba.org: Fixed bug on 6xx where we need to reload r9 with the thread_info pointer. ] Signed-off-by: Kumar Gala <galak@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-17[POWERPC] Make Book-E debug handling SMP safeKumar Gala1-9/+21
global_dbcr0 needs to be a per cpu set of save areas instead of a single global on all processors. Also, we switch to using DBCR0_IDM to determine if the user space app is being debugged as its a more consistent way. In the future we should support features like hardware breakpoint and watchpoints which will have DBCR0_IDM set but not necessarily DBCR0_IC (single step). Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2007-11-13[POWERPC] Avoid unpaired stwcx. on some processorsBecky Bruce1-0/+6
The context switch code in the kernel issues a dummy stwcx. to clear the reservation, as recommended by the architecture. However, some processors can have issues if this stwcx to address A occurs while the reservation is already held to a different address B. To avoid this problem, the dummy stwcx. needs to be paired with a dummy lwarx to the same address. This adds the dummy lwarx, and creates a cpu feature bit to indicate which cpus are affected. Tested on mpc8641_hpcn_defconfig in arch/powerpc; build tested in arch/ppc. Signed-off-by: Becky Bruce <becky.bruce@freescale.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-11-01[POWERPC] 4xx: Deal with 44x virtually tagged icacheBenjamin Herrenschmidt1-0/+23
The 44x family has an interesting "feature" which is a virtually tagged instruction cache (yuck !). So far, we haven't dealt with it properly, which means we've been mostly lucky or people didn't report the problems, unless people have been running custom patches in their distro... This is an attempt at fixing it properly. I chose to do it by setting a global flag whenever we change a PTE that was previously marked executable, and flush the entire instruction cache upon return to user space when that happens. This is a bit heavy handed, but it's hard to do more fine grained flushes as the icbi instruction, on those processor, for some very strange reasons (since the cache is virtually mapped) still requires a valid TLB entry for reading in the target address space, which isn't something I want to deal with. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2007-09-14[POWERPC] Add cpu feature for SPE handlingKumar Gala1-0/+4
Make it so that SPE support can be determined at runtime. This is similiar to how we handle AltiVec. This allows us to have SPE support built in and work on processors with and without SPE. Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2007-05-17[POWERPC] Fix COMMON symbol warningsKumar Gala1-3/+15
We get the following warnings in various ARCH=powerpc builds: WARNING: "ee_restarts" [arch/powerpc/kernel/built-in] is COMMON symbol WARNING: "fee_restarts" [arch/powerpc/kernel/built-in] is COMMON symbol WARNING: "htab_hash_searches" [arch/powerpc/mm/built-in] is COMMON symbol WARNING: "next_slot" [arch/powerpc/mm/built-in] is COMMON symbol WARNING: "mmu_hash_lock" [arch/powerpc/mm/built-in] is COMMON symbol WARNING: "primary_pteg_full" [arch/powerpc/mm/built-in] is COMMON symbol WARNING: "global_dbcr0" [arch/powerpc/kernel/built-in] is COMMON symbol Switch to moving local symbols (except mmu_hash_lock which is global) and space directive instead. Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2007-03-22[POWERPC] Remove last_syscallAnton Blanchard1-1/+0
Remove last_syscall from 32bit powerpc, its been gone in 64bit for years. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-30Remove obsolete #include <linux/config.h>Jörn Engel1-1/+0
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-04-18powerpc: Use correct sequence for putting CPU into nap modePaul Mackerras1-18/+17
We weren't using the recommended sequence for putting the CPU into nap mode. When I changed the idle loop, for some reason 7447A cpus started hanging when we put them into nap mode. Changing to the recommended sequence fixes that. The complexity here is that the recommended sequence is a loop that keeps putting the cpu back into nap mode. Clearly we need some way to break out of the loop when an interrupt (external interrupt, decrementer, performance monitor) occurs. Here we use a bit in the thread_info struct to indicate that we need this, and the exception entry code notices this and arranges for the exception to return to the value in the link register, thus breaking out of the loop. We use a new `local_flags' field in the thread_info which we can alter without needing to use an atomic update sequence. The PPC970 has the same recommended sequence, so we do the same thing there too. This also fixes a bug in the kernel stack overflow handling code on 32-bit, since it was causing a value that we needed in a register to get trashed. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27powerpc: Unify the 32 and 64 bit idle loopsPaul Mackerras1-2/+6
This unifies the 32-bit (ARCH=ppc and ARCH=powerpc) and 64-bit idle loops. It brings over the concept of having a ppc_md.power_save function from 32-bit to ARCH=powerpc, which lets us get rid of native_idle(). With this we will also be able to simplify the idle handling for pSeries and cell. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-08powerpc: Fix various syscall/signal/swapcontext bugsPaul Mackerras1-71/+24
A careful reading of the recent changes to the system call entry/exit paths revealed several problems, plus some things that could be simplified and improved: * 32-bit wasn't testing the _TIF_NOERROR bit in the syscall fast exit path, so it was only doing anything with it once it saw some other bit being set. In other words, the noerror behaviour would apply to the next system call where we had to reschedule or deliver a signal, which is not necessarily the current system call. * 32-bit wasn't doing the call to ptrace_notify in the syscall exit path when the _TIF_SINGLESTEP bit was set. * _TIF_RESTOREALL was in both _TIF_USER_WORK_MASK and _TIF_PERSYSCALL_MASK, which is odd since _TIF_RESTOREALL is only set by system calls. I took it out of _TIF_USER_WORK_MASK. * On 64-bit, _TIF_RESTOREALL wasn't causing the non-volatile registers to be restored (unless perhaps a signal was delivered or the syscall was traced or single-stepped). Thus the non-volatile registers weren't restored on exit from a signal handler. We probably got away with it mostly because signal handlers written in C wouldn't alter the non-volatile registers. * On 32-bit I simplified the code and made it more like 64-bit by making the syscall exit path jump to ret_from_except to handle preemption and signal delivery. * 32-bit was calling do_signal unnecessarily when _TIF_RESTOREALL was set - but I think because of that 32-bit was actually restoring the non-volatile registers on exit from a signal handler. * I changed the order of enabling interrupts and saving the non-volatile registers before calling do_syscall_trace_leave; now we enable interrupts first. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-01-18[PATCH] TIF_RESTORE_SIGMASK support for arch/powerpcDavid Woodhouse1-4/+4
Implement the TIF_RESTORE_SIGMASK flag in the new arch/powerpc kernel, for both 32-bit and 64-bit system call paths. Signed-off-by: David Woodhouse <dwmw2@infradead.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-13[PATCH] powerpc: Cleanup LOADADDR etc. asm macrosDavid Gibson1-1/+1
This patch consolidates the variety of macros used for loading 32 or 64-bit constants in assembler (LOADADDR, LOADBASE, SET_REG_TO_*). The idea is to make the set of macros consistent across 32 and 64 bit and to make it more obvious which is the appropriate one to use in a given situation. The new macros and their semantics are described in the comments in ppc_asm.h. In the process, we change several places that were unnecessarily using immediate loads on ppc64 to use the GOT/TOC. Likewise we cleanup a couple of places where we were clumsily subtracting PAGE_OFFSET with asm instructions to use assemble-time arithmetic or the toreal() macro instead. Signed-off-by: David Gibson <dwg@au1.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-01-09[PATCH] Fix code that saves NVGPRS in 32-bit signal frameDavid Woodhouse1-3/+3
On Thu, 2005-11-24 at 12:51 +0000, David Woodhouse wrote: > Somehow this one slipped through the cracks; when we ended up in > do_signal() on a 32-bit kernel but without having the caller-saved > registers into the regs, we didn't set the TIF_SAVE_NVGPRS flag to > ensure they got saved later. Oh, and if we actually set the flag, then we fairly quickly find out that I was a bit overzealous in copying code from entry_64.S ... :) Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-01-09[PATCH] syscall entry/exit revampDavid Woodhouse1-71/+96
This cleanup patch speeds up the null syscall path on ppc64 by about 3%, and brings the ppc32 and ppc64 code slightly closer together. The ppc64 code was checking current_thread_info()->flags twice in the syscall exit path; once for TIF_SYSCALL_T_OR_A before disabling interrupts, and then again for TIF_SIGPENDING|TIF_NEED_RESCHED etc after disabling interrupts. Now we do the same as ppc32 -- check the flags only once in the fast path, and re-enable interrupts if necessary in the ptrace case. The patch abolishes the 'syscall_noerror' member of struct thread_info and replaces it with a TIF_NOERROR bit in the flags, which is handled in the slow path. This shortens the syscall entry code, which no longer needs to clear syscall_noerror. The patch adds a TIF_SAVE_NVGPRS flag which causes the syscall exit slow path to save the non-volatile GPRs into a signal frame. This removes the need for the assembly wrappers around sys_sigsuspend(), sys_rt_sigsuspend(), et al which existed solely to save those registers in advance. It also means I don't have to add new wrappers for ppoll() and pselect(), which is what I was supposed to be doing when I got distracted into this... Finally, it unifies the ppc64 and ppc32 methods of handling syscall exit directly into a signal handler (as required by sigsuspend et al) by introducing a TIF_RESTOREALL flag which causes _all_ the registers to be reloaded from the pt_regs by taking the ret_from_exception path, instead of the normal syscall exit path which stomps on the callee-saved GPRs. It appears to pass an LTP test run on ppc64, and passes basic testing on ppc32 too. Brief tests of ptrace functionality with strace and gdb also appear OK. I wouldn't send it to Linus for 2.6.15 just yet though :) Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-28powerpc: Rename asm offset TRAP to _TRAP for 32-bitPaul Mackerras1-22/+22
... for consistency with 64-bit. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-26powerpc: Merge rtas.c into arch/powerpc/kernelPaul Mackerras1-7/+5
This splits arch/ppc64/kernel/rtas.c into arch/powerpc/kernel/rtas.c, which contains generic RTAS functions useful on any CHRP platform, and arch/powerpc/platforms/pseries/rtas-fw.[ch], which contain some pSeries-specific firmware flashing bits. The parts of rtas.c that are to do with pSeries-specific error logging are protected by a new CONFIG_RTAS_ERROR_LOGGING symbol. The inclusion of rtas.o is controlled by the CONFIG_PPC_RTAS symbol, and the relevant platforms select that. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-21[PATCH] powerpc: Merge thread_info.hDavid Gibson1-13/+12
Merge ppc32 and ppc64 versions of thread_info.h. They were pretty similar already, the chief changes are: - Instead of inline asm to implement current_thread_info(), which needs to be different for ppc32 and ppc64, we use C with an asm("r1") register variable. gcc turns it into the same asm as we used to have for both platforms. - We replace ppc32's 'local_flags' with the ppc64 'syscall_noerror' field. The noerror flag was in fact the only thing in the local_flags field anyway, so the ppc64 approach is simpler, and means we only need a load-immediate/store instead of load/mask/store when clearing the flag. - In readiness for 64k pages, when THREAD_SIZE will be less than a page, ppc64 used kmalloc() rather than get_free_pages() to allocate the kernel stack. With this patch we do the same for ppc32, since there's no strong reason not to. - For ppc64, we no longer export THREAD_SHIFT and THREAD_SIZE via asm-offsets, thread_info.h can now be safely included in asm, as on ppc32. Built and booted on G4 Powerbook (ARCH=ppc and ARCH=powerpc) and Power5 (ARCH=ppc64 and ARCH=powerpc). Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-20powerpc: Fix a branch-too-far link error for 32-bit targetsPaul Mackerras1-1/+2
Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.SPaul Mackerras1-0/+1002
The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>