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2017-08-10powerpc/lib/sstep: Add isel instruction emulationMatt Brown
This adds emulation for the isel instruction. Tested for correctness against the isel instruction and its extended mnemonics (lt, gt, eq) on ppc64le. Signed-off-by: Matt Brown <matthew.brown.dev@gmail.com> Reviewed-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10powerpc/lib/sstep: Add prty instruction emulationMatt Brown
This adds emulation for the prtyw and prtyd instructions. Tested for logical correctness against the prtyw and prtyd instructions on ppc64le. Signed-off-by: Matt Brown <matthew.brown.dev@gmail.com> Reviewed-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10powerpc/lib/sstep: Add bpermd instruction emulationMatt Brown
This adds emulation for the bpermd instruction. Tested for correctness against the bpermd instruction on ppc64le. Signed-off-by: Matt Brown <matthew.brown.dev@gmail.com> Reviewed-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10powerpc/lib/sstep: Add popcnt instruction emulationMatt Brown
This adds emulations for the popcntb, popcntw, and popcntd instructions. Tested for correctness against the popcnt{b,w,d} instructions on ppc64le. Signed-off-by: Matt Brown <matthew.brown.dev@gmail.com> Reviewed-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10powerpc/lib/sstep: Add cmpb instruction emulationMatt Brown
This patch adds emulation of the cmpb instruction, enabling xmon to emulate this instruction. Tested for correctness against the cmpb asm instruction on ppc64le. Signed-off-by: Matt Brown <matthew.brown.dev@gmail.com> Reviewed-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-07-12powerpc: Fix emulation of mfocrf in emulate_step()Anton Blanchard
From POWER4 onwards, mfocrf() only places the specified CR field into the destination GPR, and the rest of it is set to 0. The PowerPC AS from version 3.0 now requires this behaviour. The emulation code currently puts the entire CR into the destination GPR. Fix it. Fixes: 6888199f7fe5 ("[POWERPC] Emulate more instructions in software") Cc: stable@vger.kernel.org # v2.6.22+ Signed-off-by: Anton Blanchard <anton@samba.org> Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-07-12powerpc: Fix emulation of mcrf in emulate_step()Anton Blanchard
The mcrf emulation code was using the CR field number directly as the shift value, without taking into account that CR fields are numbered from 0-7 starting at the high bits. That meant it was looking at the CR fields in the reverse order. Fixes: cf87c3f6b647 ("powerpc: Emulate icbi, mcrf and conditional-trap instructions") Cc: stable@vger.kernel.org # v3.18+ Signed-off-by: Anton Blanchard <anton@samba.org> Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-23powerpc/kprobes: Convert __kprobes to NOKPROBE_SYMBOL()Naveen N. Rao
Along similar lines as commit 9326638cbee2 ("kprobes, x86: Use NOKPROBE_SYMBOL() instead of __kprobes annotation"), convert __kprobes annotation to either NOKPROBE_SYMBOL() or nokprobe_inline. The latter forces inlining, in which case the caller needs to be added to NOKPROBE_SYMBOL(). Also: - blacklist arch_deref_entry_point(), and - convert a few regular inlines to nokprobe_inline in lib/sstep.c A key benefit is the ability to detect such symbols as being blacklisted. Before this patch: $ cat /sys/kernel/debug/kprobes/blacklist | grep read_mem $ perf probe read_mem Failed to write event: Invalid argument Error: Failed to add events. $ dmesg | tail -1 [ 3736.112815] Could not insert probe at _text+10014968: -22 After patch: $ cat /sys/kernel/debug/kprobes/blacklist | grep read_mem 0xc000000000072b50-0xc000000000072d20 read_mem $ perf probe read_mem read_mem is blacklisted function, skip it. Added new events: (null):(null) (on read_mem) probe:read_mem (on read_mem) You can now use it in all perf tools, such as: perf record -e probe:read_mem -aR sleep 1 $ grep " read_mem" /proc/kallsyms c000000000072b50 t read_mem c0000000005f3b40 t read_mem $ cat /sys/kernel/debug/kprobes/list c0000000005f3b48 k read_mem+0x8 [DISABLED] Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> [mpe: Minor change log formatting, fix up some conflicts] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-03powerpc: Emulation support for load/store instructions on LERavi Bangoria
emulate_step() uses a number of underlying kernel functions that were initially not enabled for LE. This has been rectified since. So, fix emulate_step() for LE for the corresponding instructions. Cc: stable@vger.kernel.org # v3.18+ Reported-by: Anton Blanchard <anton@samba.org> Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-25powerpc/sstep: Return directly after a failed address_ok() in emulate_step()Markus Elfring
Setting err and going to ldst_done just returns 0, without using err, so just return 0 directly. We already do that for other call sites in this function. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> [mpe: Rewrite change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-12-24Replace <asm/uaccess.h> with <linux/uaccess.h> globallyLinus Torvalds
This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>' sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-11-18powerpc/lib: Fix randconfig build failure in sstep.cMichael Ellerman
Under some configs we need to explicitly include cpu_has_feature.h, otherwise we fail with: arch/powerpc/lib/sstep.c:1992:7: error: implicit declaration of function 'cpu_has_feature' Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-14powerpc: EX_TABLE macro for exception tablesNicholas Piggin
This macro is taken from s390, and allows more flexibility in changing exception table format. mpe: Put it in ppc_asm.h and only define one version using stringinfy_in_c(). Add some empty definitions and headers to keep the selftests happy. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-05-11powerpc/sstep: Fix emulation fall-throughOliver O'Halloran
There is a switch fallthough in instr_analyze() which can cause an invalid instruction to be emulated as a different, valid, instruction. The rld* (opcode 30) case extracts a sub-opcode from bits 3:1 of the instruction word. However, the only valid values of this field are 001 and 000. These cases are correctly handled, but the others are not which causes execution to fall through into case 31. Breaking out of the switch causes the instruction to be marked as unknown and allows the caller to deal with the invalid instruction in a manner consistent with other invalid instructions. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-05-11powerpc/sstep: Fix sstep.c compile on powerpcspeLennart Sorensen
Commit be96f63375a1 ("powerpc: Split out instruction analysis part of emulate_step()") introduced ldarx and stdcx into the instructions in sstep.c, which are not accepted by the assembler on powerpcspe, but does seem to be accepted by the normal powerpc assembler even in 32 bit mode. Wrap these two instructions in a __powerpc64__ check like it is everywhere else in the file. Fixes: be96f63375a1 ("powerpc: Split out instruction analysis part of emulate_step()") Signed-off-by: Len Sorensen <lsorense@csclub.uwaterloo.ca> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-11-12powerpc: Fix compilation of emulate_step()Paul Mackerras
Commit be96f63375a1 ("powerpc: Split out instruction analysis part of emulate_step()") added some calls to do_fp_load() and do_fp_store(), which fail to compile on configs with CONFIG_PPC_FPU=n and CONFIG_PPC_EMULATE_SSTEP=y. This fixes the compile by adding #ifdef CONFIG_PPC_FPU around the code that calls these functions. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc: Implement emulation of string loads and storesPaul Mackerras
The size field of the op.type word is now the total number of bytes to be loaded or stored. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc: Emulate icbi, mcrf and conditional-trap instructionsPaul Mackerras
This extends the instruction emulation done by analyse_instr() and emulate_step() to handle a few more instructions that are found in the kernel. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc: Split out instruction analysis part of emulate_step()Paul Mackerras
This splits out the instruction analysis part of emulate_step() into a separate analyse_instr() function, which decodes the instruction, but doesn't execute any load or store instructions. It does execute integer instructions and branches which can be executed purely by updating register values in the pt_regs struct. For other instructions, it returns the instruction type and other details in a new instruction_op struct. emulate_step() then uses that information to execute loads, stores, cache operations, mfmsr, mtmsr[d], and (on 64-bit) sc instructions. The reason for doing this is so that the KVM code can use it instead of having its own separate instruction emulation code. Possibly the alignment interrupt handler could also use this. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-07-22powerpc: Fix bugs in emulate_step()Paul Mackerras
This fixes some bugs in emulate_step(). First, the setting of the carry bit for the arithmetic right-shift instructions was not correct on 64-bit machines because we were masking with a mask of type int rather than unsigned long. Secondly, the sld (shift left doubleword) instruction was using the wrong instruction field for the register containing the shift count. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-06-11powerpc: fix typo 'CONFIG_PPC_CPU'Paul Bolle
Commit cd64d1697cf0 ("powerpc: mtmsrd not defined") added a check for CONFIG_PPC_CPU were a check for CONFIG_PPC_FPU was clearly intended. Fixes: cd64d1697cf0 ("powerpc: mtmsrd not defined") Signed-off-by: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-30powerpc: Fix Unaligned LE Floating Point Loads and StoresTom Musta
This patch addresses unaligned single precision floating point loads and stores in the single-step code. The old implementation improperly treated an 8 byte structure as an array of two 4 byte words, which is a classic little endian bug. Signed-off-by: Tom Musta <tmusta@gmail.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-30powerpc: Fix Unaligned Loads and StoresTom Musta
This patch modifies the unaligned access routines of the sstep.c module so that it properly reverses the bytes of storage operands in the little endian kernel kernel. This is implemented by breaking an unaligned little endian access into a combination of single byte accesses plus an overal byte reversal operation. Signed-off-by: Tom Musta <tmusta@gmail.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-09-25powerpc: Remove ksp_limit on ppc64Benjamin Herrenschmidt
We've been keeping that field in thread_struct for a while, it contains the "limit" of the current stack pointer and is meant to be used for detecting stack overflows. It has a few problems however: - First, it was never actually *used* on 64-bit. Set and updated but not actually exploited - When switching stack to/from irq and softirq stacks, it's update is racy unless we hard disable interrupts, which is costly. This is fine on 32-bit as we don't soft-disable there but not on 64-bit. Thus rather than fixing 2 in order to implement 1 in some hypothetical future, let's remove the code completely from 64-bit. In order to avoid a clutter of ifdef's, we remove the updates from C code completely during interrupt stack switching, and instead maintain it from the asm helper that is used to do the stack switching in the first place. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-08-27powerpc: Unaligned stores and stmw are broken in emulation codeTom Musta
The stmw instruction was incorrectly decoded as an update form instruction and thus the RA register was being clobbered. Also, the utility routine to write memory to unaligned addresses breaks the operation into smaller aligned accesses but was incorrectly incrementing the address by only one; it needs to increment the address by the size of the smaller aligned chunk. Signed-off-by: Tom Musta <tmusta@us.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20powerpc: Fix single step emulation of 32bit overflowed branchesMichael Neuling
Check truncate_if_32bit() on final write to nip. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-09-18powerpc/kprobe: Don't emulate store when kprobe stwu r1Tiejun Chen
We don't do the real store operation for kprobing 'stwu Rx,(y)R1' since this may corrupt the exception frame, now we will do this operation safely in exception return code after migrate current exception frame below the kprobed function stack. So we only update gpr[1] here and trigger a thread flag to mask this. Note we should make sure if we trigger kernel stack over flow. Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-20Merge branch 'merge' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc * 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (152 commits) powerpc: Fix hard CPU IDs detection powerpc/pmac: Update via-pmu to new syscore_ops powerpc/kvm: Fix the build for 32-bit Book 3S (classic) processors powerpc/kvm: Fix kvmppc_core_pending_dec powerpc: Remove last piece of GEMINI powerpc: Fix for Pegasos keyboard and mouse powerpc: Make early memory scan more resilient to out of order nodes powerpc/pseries/iommu: Cleanup ddw naming powerpc/pseries/iommu: Find windows after kexec during boot powerpc/pseries/iommu: Remove ddw property when destroying window powerpc/pseries/iommu: Add additional checks when changing iommu mask powerpc/pseries/iommu: Use correct return type in dupe_ddw_if_already_created powerpc: Remove unused/obsolete CONFIG_XICS misc: Add CARMA DATA-FPGA Programmer support misc: Add CARMA DATA-FPGA Access Driver powerpc: Make IRQ_NOREQUEST last to clear, first to set powerpc: Integrated Flash controller device tree bindings powerpc/85xx: Create dts of each core in CAMP mode for P1020RDB powerpc/85xx: Fix PCIe IDSEL for Px020RDB powerpc/85xx: P2020 DTS: re-organize dts files ...
2011-05-20sanitize <linux/prefetch.h> usageLinus Torvalds
Commit e66eed651fd1 ("list: remove prefetching from regular list iterators") removed the include of prefetch.h from list.h, which uncovered several cases that had apparently relied on that rather obscure header file dependency. So this fixes things up a bit, using grep -L linux/prefetch.h $(git grep -l '[^a-z_]prefetchw*(' -- '*.[ch]') grep -L 'prefetchw*(' $(git grep -l 'linux/prefetch.h' -- '*.[ch]') to guide us in finding files that either need <linux/prefetch.h> inclusion, or have it despite not needing it. There are more of them around (mostly network drivers), but this gets many core ones. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-04-27powerpc: Use MSR_64BIT in sstep.c, fix kprobes on BOOK3EMichael Ellerman
We check MSR_SF a lot in sstep.c, to decide if we need to emulate the truncation of values when running in 32-bit mode. Factor out that code into a helper, and convert it and the other uses to use MSR_64BIT. This fixes a bug on BOOK3E where kprobes would end up returning to a 32-bit address, because regs->nip was truncated, because (msr & MSR_SF) was false. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-09-02powerpc: mtmsrd not definedSean MacLennan
Replace the BOOK3S_64 specific mtmsrd with the generic MTMSRD macro. Only enable ldstfp when CONFIG_PPC_FPU is set. Signed-off-by: Sean MacLennan <smaclennan@pikatech.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-06-22powerpc: Emulate most Book I instructions in emulate_step()Paul Mackerras
This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2009-02-10powerpc: Don't emulate mr. instructionsAnanth N Mavinakayanahalli
Currently emulate_step() emulates mr. instructions without updating cr0 and this can be disastrous. Don't emulate mr. This bug has been around for a while, but I am not sure if its a worthy -stable candidate. I'll leave it to Ben do decide. Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2007-04-24[POWERPC] Emulate more instructions in softwareAnanth N Mavinakayanahalli
Emulate a few more instructions in software - especially useful during singlestepping (xmon/kprobes). Instructions emulated with this patch are mfcr/mtcr rX, mfxer/mtxer rX, mflr/mtlr rX, mfctr/mtctr rX and mr rA,rB. Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-11-01[POWERPC] Disallow kprobes on emulate_step and branch_takenGui,Jian
On powerpc, probing on emulate_step function will crash 2.6.18.1 when it is triggered. When kprobe is triggered, emulate_step() is on its kernel path and will cause recursive kprobe fault. And branch_taken() is called in emulate_step(). This disallows kprobes on both of them. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-30Remove obsolete #include <linux/config.h>Jörn Engel
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-03-27[PATCH] powerpc: fix various sparse warningsStephen Rothwell
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-28powerpc: Make single-stepping emulation (mostly) usable on 32-bitPaul Mackerras
The sc instruction emulation can't be done the same way on 32-bit as 64-bit yet, but this should work OK. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-09-26powerpc: Merge enough to start building in arch/powerpc.Paul Mackerras
This creates the directory structure under arch/powerpc and a bunch of Kconfig files. It does a first-cut merge of arch/powerpc/mm, arch/powerpc/lib and arch/powerpc/platforms/powermac. This is enough to build a 32-bit powermac kernel with ARCH=powerpc. For now we are getting some unmerged files from arch/ppc/kernel and arch/ppc/syslib, or arch/ppc64/kernel. This makes some minor changes to files in those directories and files outside arch/powerpc. The boot directory is still not merged. That's going to be interesting. Signed-off-by: Paul Mackerras <paulus@samba.org>