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2019-12-18x86: Fix some bugs with KVM in SE mode on Intel machines.Gabe Black
The granularity bit should be set since the segment limit should be interpreted as a number of pages, not bytes. A comment indicates that NX support is enabled, but the bit wasn't being set. That's now set to be consistent with FS mode. The SVME bit is now turned off, since Intel CPUs don't have SVME, and enabling it apparently makes them upset. Also disable CR4 bits which enable features neither gem5 nor apparently my workstation support. Change-Id: I72d5a07871dede8763b0dd188a52fe5eb6bde6ea Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/23361 Reviewed-by: Ayaz Akram <yazakram@ucdavis.edu> Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Jason Lowe-Power <jason@lowepower.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-12-10arch,cpu,sim: Push syscall number determination up to processes.Gabe Black
The logic that determines which syscall to call was built into the implementation of faults/exceptions or even into the instruction decoder, but that logic can depend on what OS is being used, and sometimes even what version, for example 32bit vs. 64bit. This change pushes that logic up into the Process objects since those already handle a lot of the aspects of emulating the guest OS. Instead, the ISA or fault implementations just notify the rest of the system that a nebulous syscall has happened, and that gets propogated upward until the process does something with it. That's very analogous to how a system call would work on a real machine. When a system call happens, the low level component which detects that should call tc->syscall(&fault), where tc is the relevant thread (or execution) context, and fault is a Fault which can ultimately be set by the system call implementation. The TC implementor (probably a CPU) will then have a chance to do whatever it needs to to handle a system call. Currently only O3 does anything special here. That implementor will end up calling the Process's syscall() method. Once in Process::syscall, the process object will use it's contextual knowledge to determine what system call is being requested. It then calls Process::doSyscall with the right syscall number, where doSyscall centralizes the common mechanism for actually retrieving and calling into the system call implementation. Jira Issue: https://gem5.atlassian.net/browse/GEM5-187 Change-Id: I937ec1ef0576142c2a182ff33ca508d77ad0e7a1 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/23176 Maintainer: Gabe Black <gabeblack@google.com> Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
2019-12-10arch: Get rid of the now unused setSyscallArg.Gabe Black
Setting syscall args isn't really something we need to do in gem5, since that will be taken care of by the code actually calling the syscall. We just need to be able to retrieve the value it put there. Jira Issue: https://gem5.atlassian.net/browse/GEM5-187 Change-Id: I0bb6d5d0207a7892414a722b3788cb70ee509582 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/23174 Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Gabe Black <gabeblack@google.com> Maintainer: Gabe Black <gabeblack@google.com>
2019-11-07x86: Replace htog and gtoh with htole and letoh.Gabe Black
We already know what endianness to use from within x86. Change-Id: Ie92568efe8b23fbb7d9edad55fef09c6302cbe62 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/22370 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Jason Lowe-Power <jason@lowepower.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-10-30arch,sim: Make copyStringArray take an explicit endianness.Gabe Black
Change-Id: I5cf4291b19dd2d2bdbbf145ad8e00994fabf5547 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/22366 Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-by: Brandon Potter <Brandon.Potter@amd.com> Maintainer: Gabe Black <gabeblack@google.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-10-12arch,base: Separate the idea of a memory image and object file.Gabe Black
A memory image can be described by an object file, but an object file is more than a memory image. Also, it makes sense to manipulate a memory image to, for instance, change how it's loaded into memory. That takes on larger implications (relocations, the entry point, symbols, etc.) when talking about the whole object file, and also modifies aspects which may not need to change. For instance if an image needs to be loaded into memory at addresses different from what's in the object file, but other things like symbols need to stay unmodified. Change-Id: Ia360405ffb2c1c48e0cc201ac0a0764357996a54 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21466 Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Brandon Potter <Brandon.Potter@amd.com> Maintainer: Gabe Black <gabeblack@google.com>
2019-10-10arch,base: Stop loading the interpreter in ElfObject.Gabe Black
The interpreter is a separate object file, and while it's convenient to hide loading it in the code which loads the main object file, it breaks the conceptual abstraction since you only asked it to load the main object file. Also, this makes every object file format reimplement the idea of loading the interpreter. Admittedly only ELF recognizes and sets up an interpreter, but other formats conceptually could too. This does move that limitted hypothetical redundancy out of the object file formats and moves it into the process objects, but I think conceptually that's where it belongs. It would also probably be pretty easy to add a method to the base Process class that would handle loading an image and also the interpreter image. This change does not (yet) separate reading symbol tables. Change-Id: I4a165eac599a9bcd30371a162379e833c4cc89b4 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21465 Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Brandon Potter <Brandon.Potter@amd.com> Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Gabe Black <gabeblack@google.com>
2019-10-10arch, base: Stop assuming object files have three segments.Gabe Black
The ObjectFile class has hardcoded assumptions that there are three segments, text, bss and data. There are some files which have one "segment" like raw files, where the entire file's contents are considered a single segment. There are also ELF files which can have an arbitrary number of segments, and those segments can hold any number of sections, including the text, data and/or bss sections. Removing this assumption frees up some object file formats from having to twist themselves to fit in that structure, possibly introducing ambiguities when some segments may fulfill multiple roles. Change-Id: I976e06a3a90ef852b17a6485e2595b006b2090d5 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21463 Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Gabe Black <gabeblack@google.com>
2019-10-09base: Rename Section to Segment, and some of its members.Gabe Black
ELF is, in my opinion, the most important object file format gem5 currently understands, and in ELF terminolgy the blob of data that needs to be loaded into memory to a particular location is called a segment. A section is a software level view of what's in a region of memory, and a single segment may contain multiple sections which happen to follow each other in memory. Change-Id: Ib810c5050723d5a96bd7550515b08ac695fb1b02 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21462 Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Gabe Black <gabeblack@google.com>
2019-05-29arch, base, dev, sim: Remove now unnecessary casts from PortProxy methods.Gabe Black
Change-Id: Ia73b2d86a10d02fa09c924a4571477bb5f200eb7 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18572 Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Jason Lowe-Power <jason@lowepower.com>
2019-04-30arch: Stop using TheISA within the ISAs.Gabe Black
We know for sure what the ISA is, so there's no need for the indirection. Change-Id: I73ff04c50890d40a4c7f40caeee746b68b846cb3 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18488 Reviewed-by: Brandon Potter <Brandon.Potter@amd.com> Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-04-28arch, sim: Simplify the AuxVector type.Gabe Black
The AuxVector type has a bunch of accessors which just give access to the underlying variables through references. We might as well just make those members accessible directly. Also, the AuxVector doesn't need to handle endianness flips itself. We can tell the byteswap mechanism how to flip an AuxVector, and let it handle that for us. This gets rid of the entire .cc file which was complicated by trying to both hide the ISA specific endianness translations, and instantiate templated functions in a .cc. Change-Id: I433cd61e73e0b067b6d628fba31be4a4ec1c4cf0 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18373 Maintainer: Gabe Black <gabeblack@google.com> Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
2019-04-22sim-se: Enhance clone for X86KvmCPUAlexandru Dutu
This changeset enables clone to work with X86KvmCPU model, which will allow running multi-threaded applications at near hardware speeds. Even though the application is multi-threaded, the KvmCPU model uses one event queue, therefore, only one hardware thread will be used, through KVM, to simulate multiple application threads. Change-Id: I2b2a7b1edb1c56eeb9c4fa0553cd236029cd53f8 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18268 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Jason Lowe-Power <jason@lowepower.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-01-31x86: Stop using/defining some ISA specific register types.Gabe Black
These have been replaced with the generic RegVal type. Change-Id: I75c1134212067dea43aa0903d813633e06f3d6c6 Reviewed-on: https://gem5-review.googlesource.com/c/14476 Reviewed-by: Gabe Black <gabeblack@google.com> Maintainer: Gabe Black <gabeblack@google.com>
2018-09-19syscall_emul: expand AuxVector classBrandon Potter
The AuxVector class is responsible for holding Process data. The data that it holds is normally setup by an OS kernel in the process address space. The purpose behind doing this is to pass in information that the process will need for various reasons. (Check out the enum in the header file for an idea of what the AuxVector holds.) The AuxVector struct was changed into a class and encapsulation methods were added to protect access to the member variables. The host ISA may have a different endianness than the simulated ISA. Since data is passed between the process address space and the simulator for auxiliary vectors, we need to worry about maintaining endianness for the right context. Change-Id: I32c5ac4b679559886e1efeb4b5483b92dfc94af9 Reviewed-on: https://gem5-review.googlesource.com/12109 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Anthony Gutierrez <anthony.gutierrez@amd.com>
2018-03-15x86: Add bitfields which can gather/scatter bases and limits.Gabe Black
Add bitfields which can gather/scatter base and limit fields within "normal" segment descriptors, and in TSS descriptors which have the same bitfields in the same positions for those two values. This centralizes the code which manages those bitfields and makes it less likely that a local implementation will be buggy. Change-Id: I9809aa626fc31388595c3d3b225c25a0ec6a1275 Reviewed-on: https://gem5-review.googlesource.com/7661 Reviewed-by: Gabe Black <gabeblack@google.com> Maintainer: Gabe Black <gabeblack@google.com>
2018-01-23x86, mem: Rewrite the multilevel page table class.Gabe Black
The new version extracts all the x86 specific aspects of the class, and builds the interface around a variable collection of template arguments which are classes that represent the different levels of the page table. The multilevel page table class is now much more ISA independent. Change-Id: Id42e168a78d0e70f80ab2438480cb6e00a3aa636 Reviewed-on: https://gem5-review.googlesource.com/7347 Reviewed-by: Brandon Potter <Brandon.Potter@amd.com> Maintainer: Gabe Black <gabeblack@google.com>
2018-01-20x86, mem: Don't try to force physical addresses on the system.Gabe Black
Use the system object to allocate physical memory instead of manually placing certain structures and then forcing the system to start other allocations after them in physical memory. Change-Id: Ie18c81645c3b648c64a6d7a649a0e50f7028f344 Reviewed-on: https://gem5-review.googlesource.com/7346 Maintainer: Gabe Black <gabeblack@google.com> Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
2018-01-20x86, mem: Get rid of PageTableOps::getBasePtr.Gabe Black
Pass this constant into the page table constructor. Change-Id: Icbf730f18d9dfcfebd10a196f7f799514728b0fb Reviewed-on: https://gem5-review.googlesource.com/7345 Maintainer: Gabe Black <gabeblack@google.com> Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
2018-01-20x86, mem: Pass the multi level page table layout in as a parameter.Gabe Black
Don't get it from a global constant declared in an ISA header file. Change-Id: Ie19440abdd76500a5e12e6791e6f755ad9e95af3 Reviewed-on: https://gem5-review.googlesource.com/7344 Maintainer: Gabe Black <gabeblack@google.com> Reviewed-by: Brandon Potter <Brandon.Potter@amd.com> Reviewed-by: Alexandru Duțu <alexandru.dutu@amd.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
2018-01-19arch, mem, sim: Consolidate and rename the SE mode page table classes.Gabe Black
Now that Nothing inherits from PageTableBase directly, it can be merged into FuncPageTable. This change also takes the opportunity to rename the combined class to EmulationPageTable which lets you know that it's specifically for SE mode. Also remove the page table entry cache since it doesn't seem to actually improve performance. The TLBs likely absorb the majority of the locality, essentially acting like a cache like they would in real hardware. Change-Id: If1bcb91aed08686603bf7bee37298c0eee826e13 Reviewed-on: https://gem5-review.googlesource.com/7342 Reviewed-by: Brandon Potter <Brandon.Potter@amd.com> Maintainer: Gabe Black <gabeblack@google.com>
2018-01-11arch,mem: Remove the default value for page size.Gabe Black
This breaks one more architecture dependence outside of the ISAs. Change-Id: I071f9ed73aef78e1cd1752247c183e30854b2d28 Reviewed-on: https://gem5-review.googlesource.com/6982 Maintainer: Gabe Black <gabeblack@google.com> Reviewed-by: Alexandru Duțu <alexandru.dutu@amd.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
2018-01-11arch,mem: Move page table construction into the arch classes.Gabe Black
This gets rid of an awkward NoArchPageTable class, and also gives the arch a place to inject ISA specific parameters (specifically page size) without having to have TheISA:: in the generic version of these types. Change-Id: I1412f303460d5c43dafdb9b3cd07af81c908a441 Reviewed-on: https://gem5-review.googlesource.com/6981 Reviewed-by: Alexandru Duțu <alexandru.dutu@amd.com> Maintainer: Gabe Black <gabeblack@google.com>
2017-12-04misc: Rename misc.(hh|cc) to logging.(hh|cc)Gabe Black
These files aren't a collection of miscellaneous stuff, they're the definition of the Logger interface, and a few utility macros for calling into that interface (panic, warn, etc.). Change-Id: I84267ac3f45896a83c0ef027f8f19c5e9a5667d1 Reviewed-on: https://gem5-review.googlesource.com/6226 Reviewed-by: Brandon Potter <Brandon.Potter@amd.com> Maintainer: Gabe Black <gabeblack@google.com>
2017-03-09style: Correct some style issuesBrandon Potter
This changeset fixes line alignment issues, spacing, spelling, etc. for files that are used during SE Mode. Change-Id: Ie61b8d0eb4ebb5af554d72f1297808027833616e Reviewed-on: https://gem5-review.googlesource.com/2264 Maintainer: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Tony Gutierrez <anthony.gutierrez@amd.com> Reviewed-by: Michael LeBeane <Michael.Lebeane@amd.com> Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-by: Pierre-Yves Péneau <pierre-yves.peneau@lirmm.fr>
2017-03-09syscall-emul: Move memState into its own fileBrandon Potter
The Process class is full of implementation details and structures related to SE Mode. This changeset factors out an internal class from Process and moves it into a separate file. The purpose behind doing this is to clean up the code and make it a bit more modular. Change-Id: Ic6941a1657751e8d51d5b6b1dcc04f1195884280 Reviewed-on: https://gem5-review.googlesource.com/2263 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2017-02-27syscall_emul: [PATCH 15/22] add clone/execve for threading and multiprocess ↵Brandon Potter
simulations Modifies the clone system call and adds execve system call. Requires allowing processes to steal thread contexts from other processes in the same system object and the ability to detach pieces of process state (such as MemState) to allow dynamic sharing.
2017-02-27x86: remove unnecessary parameter from functionsBrandon Potter
2015-07-20syscall_emul: [patch 13/22] add system call retry capabilityBrandon Potter
This changeset adds functionality that allows system calls to retry without affecting thread context state such as the program counter or register values for the associated thread context (when system calls return with a retry fault). This functionality is needed to solve problems with blocking system calls in multi-process or multi-threaded simulations where information is passed between processes/threads. Blocking system calls can cause deadlock because the simulator itself is single threaded. There is only a single thread servicing the event queue which can cause deadlock if the thread hits a blocking system call instruction. To illustrate the problem, consider two processes using the producer/consumer sharing model. The processes can use file descriptors and the read and write calls to pass information to one another. If the consumer calls the blocking read system call before the producer has produced anything, the call will block the event queue (while executing the system call instruction) and deadlock the simulation. The solution implemented in this changeset is to recognize that the system calls will block and then generate a special retry fault. The fault will be sent back up through the function call chain until it is exposed to the cpu model's pipeline where the fault becomes visible. The fault will trigger the cpu model to replay the instruction at a future tick where the call has a chance to succeed without actually going into a blocking state. In subsequent patches, we recognize that a syscall will block by calling a non-blocking poll (from inside the system call implementation) and checking for events. When events show up during the poll, it signifies that the call would not have blocked and the syscall is allowed to proceed (calling an underlying host system call if necessary). If no events are returned from the poll, we generate the fault and try the instruction for the thread context at a distant tick. Note that retrying every tick is not efficient. As an aside, the simulator has some multi-threading support for the event queue, but it is not used by default and needs work. Even if the event queue was completely multi-threaded, meaning that there is a hardware thread on the host servicing a single simulator thread contexts with a 1:1 mapping between them, it's still possible to run into deadlock due to the event queue barriers on quantum boundaries. The solution of replaying at a later tick is the simplest solution and solves the problem generally.
2016-11-09syscall_emul: [patch 9/22] remove unused global variable (num_processes)Brandon Potter
2016-11-09syscall_emul: [patch 8/22] refactor process classBrandon Potter
Moves aux_vector into its own .hh and .cc files just to get it out of the already crowded Process files. Arguably, it could stay there, but it's probably better just to move it and give it files. The changeset looks ugly around the Process header file, but the goal here is to move methods and members around so that they're not defined randomly throughout the entire header file. I expect this is likely one of the reasons why I several unused variables related to this class. So, the methods are declared first followed by members. I've tried to aggregate them together so that similar entries reside near one another. There are other changes coming to this code so this is by no means the final product.
2016-11-09syscall_emul: [patch 5/22] remove LiveProcess class and use Process insteadBrandon Potter
The EIOProcess class was removed recently and it was the only other class which derived from Process. Since every Process invocation is also a LiveProcess invocation, it makes sense to simplify the organization by combining the fields from LiveProcess into Process.
2016-11-09style: [patch 3/22] reduce include dependencies in some headersBrandon Potter
Used cppclean to help identify useless includes and removed them. This involved erroneously included headers, but also cases where forward declarations could have been used rather than a full include.
2016-11-09syscall_emul: [patch 2/22] move SyscallDesc into its own .hh and .ccBrandon Potter
The class was crammed into syscall_emul.hh which has tons of forward declarations and template definitions. To clean it up a bit, moved the class into separate files and commented the class with doxygen style comments. Also, provided some encapsulation by adding some accessors and a mutator. The syscallreturn.hh file was renamed syscall_return.hh to make it consistent with other similarly named files in the src/sim directory. The DPRINTF_SYSCALL macro was moved into its own header file with the include the Base and Verbose flags as well. --HG-- rename : src/sim/syscallreturn.hh => src/sim/syscall_return.hh
2016-11-09style: [patch 1/22] use /r/3648/ to reorganize includesBrandon Potter
2016-10-26hsail,gpu-compute: fixes to appease clang++Tony Gutierrez
fixes to appease clang++. tested on: Ubuntu clang version 3.5.0-4ubuntu2~trusty2 (tags/RELEASE_350/final) (based on LLVM 3.5.0) Ubuntu clang version 3.6.0-2ubuntu1~trusty1 (tags/RELEASE_360/final) (based on LLVM 3.6.0) the fixes address the following five issues: 1) the exec continuations in gpu_static_inst.hh were marked as protected when they should be public. here we mark them as public 2) the Abs instruction uses std::abs() in its execute method. because Abs is templated, it can also operate on U32 and U64, types, which cause Abs::execute() to pass uint32_t and uint64_t types to std::abs() respectively. this triggers a warning because std::abs() has no effect in this case. to rememdy this we add template specialization for the execute() method of Abs when its template paramter is U32 or U64. 3) Some potocols that utilize the code in cprintf.hh were missing includes to BoolVec.hh, which defines operator<< for the BoolVec type. This would cause issues when the generated code would try to pass a BoolVec type to a method in cprintf.hh that used operator<< on an instance of a BoolVec. 4) Surprise, clang doesn't like it when you clobber all the bits in a newly allocated object. I.e., this code: tlb = new GpuTlbEntry\[size\]; std::memset(tlb, 0, sizeof(GpuTlbEntry) \* size); Let's use std::vector to track the TLB entries in the GpuTlb now... 5) There were a few variables used only in DPRINTFs, so we mark them with M5_VAR_USED.
2016-03-17base: support dynamic loading of Linux ELF objects in SE modeBrandon Potter
2016-03-17syscall_emul: update x86 mmap base addressBrandon Potter
2016-03-17syscall_emul: move mmapGrowsDown() to LiveProcessSteve Reinhardt
The mmapGrowsDown() method was a static method on the OperatingSystem class (and derived classes), which worked OK for the templated syscall emulation methods, but made it hard to access elsewhere. This patch moves the method to be a virtual function on the LiveProcess method, where it can be overridden for specific platforms (for now, Alpha). This patch also changes the value of mmapGrowsDown() from being false by default and true only on X86Linux32 to being true by default and false only on Alpha, which seems closer to reality (though in reality most people use ASLR and this doesn't really matter anymore). In the process, also got rid of the unused mmap_start field on LiveProcess and OperatingSystem mmapGrowsUp variable.
2016-03-17syscall_emul: fix bugs for mmap2 system call and x86-32 syscallsBrandon Potter
2016-02-06syscall_emul: fix bug in aux vector initializationSteve Reinhardt
Writing 16 bytes from an 8-byte source value is a bad idea. This doesn't appear to have broken anything, but showed up as spurious differences when tracediffing runs.
2016-02-06style: fix missing spaces in control statementsSteve Reinhardt
Result of running 'hg m5style --skip-all --fix-control -a'.
2016-02-06style: remove trailing whitespaceSteve Reinhardt
Result of running 'hg m5style --skip-all --fix-white -a'.
2014-12-02x86: Clean up style in process.cc.Gabe Black
2014-11-23x86: Segment initialization to support KvmCPU in SEAlexandru Dutu
This patch sets up low and high privilege code and data segments and places them in the following order: cs low, ds low, ds, cs, in the GDT. Additionally, a syscall and page fault handler for KvmCPU in SE mode are defined. The order of the segment selectors in GDT is required in this manner for interrupt handling to work properly. Segment initialization is done for all the thread contexts.
2014-09-03arch: Cleanup unused ISA traits constantsAndreas Hansson
This patch prunes unused values, and also unifies how the values are defined (not using an enum for ALPHA), aligning the use of int vs Addr etc. The patch also removes the duplication of PageBytes/PageShift and VMPageSize/LogVMPageSize. For all ISAs the two pairs had identical values and the latter has been removed.
2014-05-12syscall emulation: clean up & comment SyscallReturnSteve Reinhardt
2013-04-23x86: corrects vsyscall address for gettimeofdayMichael Levenhagen
The vsyscall address for gettimeofday is 0xffffffffff600000ul. The offset therefore should be 0x0 instead of 0x410. This can be cross checked with the file sysdeps/unix/sysv/linux/x86_64/gettimeofday.c in source of glibc. Committed by: Nilay Vaish <nilay@cs.wisc.edu>
2012-05-27X86: Move the GDT down to where it can be accessed in 32 bit mode.Gabe Black
The GDT can be accessed by user level software running in compatibility mode by moving segment selectors into segment registers. The GDT needs to be set up at an address accessible in this mode.
2012-02-24MEM: Make port proxies use references rather than pointersAndreas Hansson
This patch is adding a clearer design intent to all objects that would not be complete without a port proxy by making the proxies members rathen than dynamically allocated. In essence, if NULL would not be a valid value for the proxy, then we avoid using a pointer to make this clear. The same approach is used for the methods using these proxies, such as loadSections, that now use references rather than pointers to better reflect the fact that NULL would not be an acceptable value (in fact the code would break and that is how this patch started out). Overall the concept of "using a reference to express unconditional composition where a NULL pointer is never valid" could be done on a much broader scale throughout the code base, but for now it is only done in the locations affected by the proxies.