summaryrefslogtreecommitdiff
path: root/arch/powerpc/kernel/align.c
AgeCommit message (Collapse)Author
2013-09-26powerpc: Handle unaligned ldbrx/stdbrxAnton Blanchard
commit 230aef7a6a23b6166bd4003bfff5af23c9bd381f upstream. Normally when we haven't implemented an alignment handler for a load or store instruction the process will be terminated. The alignment handler uses the DSISR (or a pseudo one) to locate the right handler. Unfortunately ldbrx and stdbrx overlap lfs and stfs so we incorrectly think ldbrx is an lfs and stdbrx is an stfs. This bug is particularly nasty - instead of terminating the process we apply an incorrect fixup and continue on. With more and more overlapping instructions we should stop creating a pseudo DSISR and index using the instruction directly, but for now add a special case to catch ldbrx/stdbrx. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-03-28Disintegrate asm/system.h for PowerPCDavid Howells
Disintegrate asm/system.h for PowerPC. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> cc: linuxppc-dev@lists.ozlabs.org
2010-09-02powerpc: Remove fpscr use from [kvm_]cvt_{fd,df}Andreas Schwab
Neither lfs nor stfs touch the fpscr, so remove the restore/save of it around them. Signed-off-by: Andreas Schwab <schwab@linux-m68k.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-12-18powerpc: Handle VSX alignment faults correctly in little-endian modeNeil Campbell
This patch fixes the handling of VSX alignment faults in little-endian mode (the current code assumes the processor is in big-endian mode). The patch also makes the handlers clear the top 8 bytes of the register when handling an 8 byte VSX load. This is based on 2.6.32. Signed-off-by: Neil Campbell <neilc@linux.vnet.ibm.com> Cc: <stable@kernel.org> Acked-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-10-28powerpc: Create PPC_WARN_ALIGNMENT to match PPC_WARN_EMULATEDAnton Blanchard
perf_event wants a separate event for alignment and emulation faults, so create another emulation event. This will make it easy to hook in perf_event at one spot. We pass in regs which will be required for these events. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2009-05-21powerpc: Keep track of emulated instructionsGeert Uytterhoeven
If CONFIG_PPC_EMULATED_STATS is enabled, make available counters for the various classes of emulated instructions under /sys/kernel/debug/powerpc/emulated_instructions/ (assumed debugfs is mounted on /sys/kernel/debug). Optionally (controlled by /sys/kernel/debug/powerpc/emulated_instructions/do_warn), rate-limited warnings can be printed to the console when instructions are emulated. Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-02-23powerpc: Fix load/store float double alignment handlerMichael Neuling
When we introduced VSX, we changed the way FPRs are stored in the thread_struct. Unfortunately we missed the load/store float double alignment handler code when updating how we access FPRs in the thread_struct. Below fixes this and merges the little/big endian case. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-02-23powerpc: Add alignment handler for new lfiwzx instructionMichael Neuling
lfiwzx is a new floating point load instruction in 2.06 that needs an alignment handler for Linux. Turns out to be the worlds easiest handler to add. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-02-13powerpc/vsx: Fix VSX alignment handler for regs 32-63Michael Neuling
Fix the VSX alignment handler for VSX registers > 32. 32-63 are stored in the VMX part of the thread_struct not the FPR part. Signed-off-by: Michael Neuling <mikey@neuling.org> CC: stable@kernel.org (2.6.27 & .28 please) Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-09-03powerpc: Fix uninitialised variable in VSX alignment codeMichael Neuling
This fixes an uninitialised variable in the VSX alignment code. It can cause warnings from GCC (noticed with gcc-4.1.1). Gcc is actually correct in this instance, and this bug could cause the alignment interrupt handler to send a SIGSEGV to the process on a legitimate access. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-15powerpc: Add VSX load/store alignment exception handlerMichael Neuling
VSX loads and stores will take an alignment exception when the address is not on a 4 byte boundary. This add support for these alignment exceptions and will emulate the requested load or store. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-09powerpc: remove unused variable in emulate_fp_pairMichael Neuling
regs is not used in emulate_fp_pair so remove it. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-01powerpc: Add macros to access floating point registers in thread_struct.Michael Neuling
We are going to change where the floating point registers are stored in the thread_struct, so in preparation add some macros to access the floating point registers. Update all code to use these new macros. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-09-14[POWERPC] Handle alignment faults on SPE load/store instructionsKumar Gala
This adds code to handle alignment traps generated by the following SPE (signal processing engine) load/store instructions, by emulating the instruction in the kernel (as is done for other instructions that generate alignment traps): evldd[x] Vector Load Double Word into Double Word [Indexed] evldw[x] Vector Load Double into Two Words [Indexed] evldh[x] Vector Load Double into Four Half Words [Indexed] evlhhesplat[x] Vector Load Half Word into Half Words Even and Splat [Indexed] evlhhousplat[x] Vector Load Half Word into Half Word Odd Unsigned and Splat [Indexed] evlhhossplat[x] Vector Load Half Word into Half Word Odd Signed and Splat [Indexed] evlwhe[x] Vector Load Word into Two Half Words Even [Indexed] evlwhou[x] Vector Load Word into Two Half Words Odd Unsigned (zero-extended) [Indexed] evlwhos[x] Vector Load Word into Two Half Words Odd Signed (with sign extension) [Indexed] evlwwsplat[x] Vector Load Word into Word and Splat [Indexed] evlwhsplat[x] Vector Load Word into Two Half Words and Splat [Indexed] evstdd[x] Vector Store Double of Double [Indexed] evstdw[x] Vector Store Double of Two Words [Indexed] evstdh[x] Vector Store Double of Four Half Words [Indexed] evstwhe[x] Vector Store Word of Two Half Words from Even [Indexed] evstwho[x] Vector Store Word of Two Half Words from Odd [Indexed] evstwwe[x] Vector Store Word of Word from Even [Indexed] evstwwo[x] Vector Store Word of Word from Odd [Indexed] Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2007-08-17[POWERPC] Handle alignment faults on new FP load/store instructionsPaul Mackerras
This adds code to handle alignment traps generated by the following new floating-point load/store instructions, by emulating the instruction in the kernel (as is done for other instructions that generate alignment traps): lfiwax load floating-point as integer word algebraic indexed stfiwx store floating-point as integer word indexed lfdp load floating-point double pair lfdpx load floating-point double pair indexed stfdp store floating-point double pair stfdpx store floating-point double pair indexed All these except stfiwx are new in POWER6. lfdp/lfdpx/stfdp/stfdpx load and store 16 bytes of memory into an even/odd FP register pair. In little-endian mode each 8-byte value is byte-reversed separately (i.e. not as a 16-byte unit). lfiwax/stfiwx load or store the lower 4 bytes of a floating-point register from/to memory; lfiwax sets the upper 4 bytes of the FP register to the sign extension of the value loaded. Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-04-13[POWERPC] Alignment exception uses __get/put_user_inatomicBenjamin Herrenschmidt
Make the alignment exception handler use the new _inatomic variants of __get/put_user. This fixes erroneous warnings in the very rare cases where we manage to have copy_tofrom_user_inatomic() trigger an alignment exception. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> arch/powerpc/kernel/align.c | 56 ++++++++++++++++++++++++-------------------- 1 file changed, 31 insertions(+), 25 deletions(-) Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-09[PATCH] powerpc: Implement support for setting little-endian mode via prctlPaul Mackerras
This adds the PowerPC part of the code to allow processes to change their endian mode via prctl. This also extends the alignment exception handler to be able to fix up alignment exceptions that occur in little-endian mode, both for "PowerPC" little-endian and true little-endian. We always enter signal handlers in big-endian mode -- the support for little-endian mode does not amount to the creation of a little-endian user/kernel ABI. If the signal handler returns, the endian mode is restored to what it was when the signal was delivered. We have two new kernel CPU feature bits, one for PPC little-endian and one for true little-endian. Most of the classic 32-bit processors support PPC little-endian, and this is reflected in the CPU feature table. There are two corresponding feature bits reported to userland in the AT_HWCAP aux vector entry. This is based on an earlier patch by Anton Blanchard. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-18[PATCH] powerpc: merge align.cBenjamin Herrenschmidt
This patch merges align.c, the result isn't quite what was in ppc64 nor what was in ppc32 :) It should implement all the functionalities of both though. Kumar, since you played with that in the past, I suppose you have some test cases for verifying that it works properly before I dig out the 601 machine ? :) Since it's likely that I won't be able to test all scenario, code inspection is much welcome. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>