Eric Lee / linux-smarc-t335x-v3.2

22 Jul, 2011

2 commits

12 Oct, 2009

1 commit

30 Jul, 2009

1 commit

  • 2e04ef769   lguest: fix comment style ... Browse Code »

    I don't really notice it (except to begrudge the extra vertical
    space), but Ingo does. And he pointed out that one excuse of lguest
    is as a teaching tool, it should set a good example.

    Signed-off-by: Rusty Russell
    Cc: Ingo Molnar

    Rusty Russell
     

12 Jun, 2009

4 commits

  • 9f155a9b3   lguest: allow any process to send interrupts ... Browse Code »

    We currently only allow the Launcher process to send interrupts, but it
    as we already send interrupts from the hrtimer, it's a simple matter of
    extracting that code into a common set_interrupt routine.

    As we switch to a thread per virtqueue, this avoids a bottleneck through the
    main Launcher process.

    Signed-off-by: Rusty Russell

    Rusty Russell
     
  • a32a8813d   lguest: improve interrupt handling, speed up stream networking ... Browse Code »

    lguest never checked for pending interrupts when enabling interrupts, and
    things still worked. However, it makes a significant difference to TCP
    performance, so it's time we fixed it by introducing a pending_irq flag
    and checking it on irq_restore and irq_enable.

    These two routines are now too big to patch into the 8/10 bytes
    patch space, so we drop that code.

    Note: The high latency on interrupt delivery had a very curious
    effect: once everything else was optimized, networking without GSO was
    faster than networking with GSO, since more interrupts were sent and
    hence a greater chance of one getting through to the Guest!

    Note2: (Almost) Closing the same loophole for iret doesn't have any
    measurable effect, so I'm leaving that patch for the moment.

    Before:
    1GB tcpblast Guest->Host: 30.7 seconds
    1GB tcpblast Guest->Host (no GSO): 76.0 seconds

    After:
    1GB tcpblast Guest->Host: 6.8 seconds
    1GB tcpblast Guest->Host (no GSO): 27.8 seconds

    Signed-off-by: Rusty Russell

    Rusty Russell
     
  • abd41f037   lguest: fix race in halt code ... Browse Code »

    When the Guest does the LHCALL_HALT hypercall, we go to sleep, expecting
    that a timer or the Waker will wake_up_process() us.

    But we do it in a stupid way, leaving a classic missing wakeup race.

    So split maybe_do_interrupt() into interrupt_pending() and
    try_deliver_interrupt(), and check maybe_do_interrupt() and the
    "break_out" flag before calling schedule.

    Signed-off-by: Rusty Russell

    Rusty Russell
     
  • a6c372de6   lguest: fix lguest wake on guest clock tick, or fd activity ... Browse Code »

    The Launcher could be inside the Guest on another CPU; wake_up_process
    will do nothing because it is "running". kick_process will knock it
    back into our kernel in this case, otherwise we'll miss it until the
    next guest exit.

    Signed-off-by: Rusty Russell

    Rusty Russell
     

30 Mar, 2009

2 commits

24 Dec, 2008

1 commit

  • b77b881f2   x86: fix lguest used_vectors breakage, -v2 ... Browse Code »

    Impact: fix lguest, clean up

    32-bit lguest used used_vectors to record vectors, but that model of
    allocating vectors changed and got broken, after we changed vector
    allocation to a per_cpu array.

    Try enable that for 64bit, and the array is used for all vectors that
    are not managed by vector_irq per_cpu array.

    Also kill system_vectors[], that is now a duplication of the
    used_vectors bitmap.

    [ merged in cpus4096 due to io_apic.c cpumask changes. ]
    [ -v2, fix build failure ]

    Signed-off-by: Yinghai Lu
    Signed-off-by: Ingo Molnar
    Signed-off-by: Ingo Molnar

    Yinghai Lu
     

29 Jul, 2008

1 commit

  • 0c12091d8   lguest: Guest int3 fix ... Browse Code »

    Ron Minnich noticed that guest userspace gets a GPF when it tries to int3:
    we need to copy the privilege level from the guest-supplied IDT to the real
    IDT. int3 is the only common case where guest userspace expects to invoke
    an interrupt, so that's the symptom of failing to do this.

    Signed-off-by: Rusty Russell

    Rusty Russell
     

28 Mar, 2008

1 commit

30 Jan, 2008

9 commits

25 Oct, 2007

1 commit

23 Oct, 2007

5 commits

  • 2d37f94a2   generalize lgread_u32/lgwrite_u32. ... Browse Code »

    Jes complains that page table code still uses lgread_u32 even though
    it now uses general kernel pte types. The best thing to do is to
    generalize lgread_u32 and lgwrite_u32.

    This means we lose the efficiency of getuser(). We could potentially
    regain it if we used __copy_from_user instead of copy_from_user, but
    I'm not certain that our range check is equivalent to access_ok() on
    all platforms.

    Signed-off-by: Rusty Russell
    Acked-by: Jes Sorensen

    Rusty Russell
     
  • 47436aa4a   Boot with virtual == physical to get closer to native Linux. ... Browse Code »

    1) This allows us to get alot closer to booting bzImages.

    2) It means we don't have to know page_offset.

    3) The Guest needs to modify the boot pagetables to create the
    PAGE_OFFSET mapping before jumping to C code.

    4) guest_pa() walks the page tables rather than using page_offset.

    5) We don't use page_offset to figure out whether to emulate: it was
    always kinda quesationable, and won't work for instructions done
    before remapping (bzImage unpacking in particular).

    6) We still want the kernel address for tlb flushing: have the initial
    hypercall give us that, too.

    Signed-off-by: Rusty Russell

    Rusty Russell
     
  • c18acd73f   Allow guest to specify syscall vector to use. ... Browse Code »

    (Based on Ron Minnich's LGUEST_PLAN9_SYSCALL patch).

    This patch allows Guests to specify what system call vector they want,
    and we try to reserve it. We only allow one non-Linux system call
    vector, to try to avoid DoS on the Host.

    Signed-off-by: Rusty Russell

    Rusty Russell
     
  • 625efab1c   Move i386 part of core.c to x86/core.c. ... Browse Code »

    Separate i386 architecture specific from core.c and move it to
    x86/core.c and add x86/lguest.h header file to match.

    Signed-off-by: Jes Sorensen
    Signed-off-by: Rusty Russell

    Jes Sorensen
     
  • 56adbe9dd   Make shadow IDT a complete IDT with 256 entries. ... Browse Code »

    This simplifies the code a little, in preparation for allowing
    alternate system call vectors in guests (Plan 9 uses 0x40).

    Signed-off-by: Rusty Russell

    Rusty Russell
     

31 Aug, 2007

1 commit

  • 8057d763e   Fix lguest page-pinning logic ("lguest: bad stack page 0xc057a000") ... Browse Code »

    If the stack pointer is 0xc057a000, then the first stack page is at
    0xc0579000 (the stack pointer is decremented before use). Not
    calculating this correctly caused guests with CONFIG_DEBUG_PAGEALLOC=y
    to be killed with a "bad stack page" message: the initial kernel stack
    was just proceeding the .smp_locks section which
    CONFIG_DEBUG_PAGEALLOC marks read-only when freeing.

    Thanks to Frederik Deweerdt for the bug report!

    Signed-off-by: Rusty Russell
    Signed-off-by: Linus Torvalds

    Rusty Russell
     

09 Aug, 2007

1 commit

  • 0d027c01c   lguest: Fix Malicious Guest GDT Host Crash ... Browse Code »

    If a Guest makes hypercall which sets a GDT entry to not present, we
    currently set any segment registers using that GDT entry to 0.
    Unfortunately, this is not sufficient: there are other ways of
    altering GDT entries which will cause a fault.

    The correct solution to do what Linux does: let them set any GDT value
    they want and handle the #GP when popping causes a fault. This has
    the added benefit of making our Switcher slightly more robust in the
    case of any other bugs which cause it to fault.

    We kill the Guest if it causes a fault in the Switcher: it's the
    Guest's responsibility to make sure it's not using segments when it
    changes them.

    Signed-off-by: Rusty Russell
    Signed-off-by: Linus Torvalds

    Rusty Russell
     

29 Jul, 2007

1 commit

  • 6c8dca5d5   Provide timespec to guests rather than jiffies clock. ... Browse Code »

    A non-periodic clock_event_device and the "jiffies" clock don't mix well:
    tick_handle_periodic() can go into an infinite loop.

    Currently lguest guests use the jiffies clock when the TSC is
    unusable. Instead, make the Host write the current time into the lguest
    page on every interrupt. This doesn't cost much but is more precise
    and at least as accurate as the jiffies clock. It also gets rid of
    the GET_WALLCLOCK hypercall.

    Also, delay setting sched_clock until our clock is set up, otherwise
    the early printk timestamps can go backwards (not harmful, just ugly).

    Signed-off-by: Rusty Russell
    Signed-off-by: Linus Torvalds

    Rusty Russell
     

27 Jul, 2007

3 commits

21 Jul, 2007

1 commit

  • e5faff45b   lguest: fix sense if IF flag on interrupt injection ... Browse Code »

    The sense of the IF bit is backwards in the host interrupt handling.

    This means we always save "IF=1" on the stack when injecting an
    interrupt. It turns out this is almost always correct (unless the
    guest is taking a page fault in an interrupt due to an unpopulated
    vmalloc mapping), so went unnoticed.

    Signed-off-by: Rusty Russell
    Signed-off-by: Linus Torvalds

    Rusty Russell
     

20 Jul, 2007

1 commit

  • d7e28ffe6   lguest: the host code ... Browse Code »

    This is the code for the "lg.ko" module, which allows lguest guests to
    be launched.

    [akpm@linux-foundation.org: update for futex-new-private-futexes]
    [akpm@linux-foundation.org: build fix]
    [jmorris@namei.org: lguest: use hrtimers]
    [akpm@linux-foundation.org: x86_64 build fix]
    Signed-off-by: Rusty Russell
    Cc: Andi Kleen
    Cc: Eric Dumazet
    Cc: Thomas Gleixner
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Rusty Russell