1. 30 3月, 2009 1 次提交
  2. 09 3月, 2009 2 次提交
    • R
      lguest: fix for CONFIG_SPARSE_IRQ=y · 6db6a5f3
      Rusty Russell 提交于
      Impact: remove lots of lguest boot WARN_ON() when CONFIG_SPARSE_IRQ=y
      
      We now need to call irq_to_desc_alloc_cpu() before
      set_irq_chip_and_handler_name(), but we can't do that from init_IRQ (no
      kmalloc available).
      
      So do it as we use interrupts instead.  Also means we only alloc for
      irqs we use, which was the intent of CONFIG_SPARSE_IRQ anyway.
      Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
      Cc: Ingo Molnar <mingo@redhat.com>
      6db6a5f3
    • R
      lguest: fix crash 'unhandled trap 13 at <native_read_msr_safe>' · cbd88c8e
      Rusty Russell 提交于
      Impact: fix lguest boot crash on modern Intel machines
      
      The code in early_init_intel does:
      
      	if (c->x86 > 6 || (c->x86 == 6 && c->x86_model >= 0xd)) {
      		u64 misc_enable;
      
      		rdmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
      
      And that rdmsr faults (not allowed from non-0 PL).  We can get around
      this by mugging the family ID part of the cpuid.  5 seems like a good
      number.
      
      Of course, this is a hack (how very lguest!).  We could just indicate
      that we don't support MSRs, or implement lguest_rdmst.
      Reported-by: NPatrick McHardy <kaber@trash.net>
      Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
      Tested-by: NPatrick McHardy <kaber@trash.net>
      cbd88c8e
  3. 18 2月, 2009 1 次提交
  4. 17 2月, 2009 1 次提交
  5. 10 2月, 2009 1 次提交
    • T
      x86: make lazy %gs optional on x86_32 · ccbeed3a
      Tejun Heo 提交于
      Impact: pt_regs changed, lazy gs handling made optional, add slight
              overhead to SAVE_ALL, simplifies error_code path a bit
      
      On x86_32, %gs hasn't been used by kernel and handled lazily.  pt_regs
      doesn't have place for it and gs is saved/loaded only when necessary.
      In preparation for stack protector support, this patch makes lazy %gs
      handling optional by doing the followings.
      
      * Add CONFIG_X86_32_LAZY_GS and place for gs in pt_regs.
      
      * Save and restore %gs along with other registers in entry_32.S unless
        LAZY_GS.  Note that this unfortunately adds "pushl $0" on SAVE_ALL
        even when LAZY_GS.  However, it adds no overhead to common exit path
        and simplifies entry path with error code.
      
      * Define different user_gs accessors depending on LAZY_GS and add
        lazy_save_gs() and lazy_load_gs() which are noop if !LAZY_GS.  The
        lazy_*_gs() ops are used to save, load and clear %gs lazily.
      
      * Define ELF_CORE_COPY_KERNEL_REGS() which always read %gs directly.
      
      xen and lguest changes need to be verified.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
      Cc: Rusty Russell <rusty@rustcorp.com.au>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      ccbeed3a
  6. 31 1月, 2009 1 次提交
    • J
      x86/paravirt: add register-saving thunks to reduce caller register pressure · ecb93d1c
      Jeremy Fitzhardinge 提交于
      Impact: Optimization
      
      One of the problems with inserting a pile of C calls where previously
      there were none is that the register pressure is greatly increased.
      The C calling convention says that the caller must expect a certain
      set of registers may be trashed by the callee, and that the callee can
      use those registers without restriction.  This includes the function
      argument registers, and several others.
      
      This patch seeks to alleviate this pressure by introducing wrapper
      thunks that will do the register saving/restoring, so that the
      callsite doesn't need to worry about it, but the callee function can
      be conventional compiler-generated code.  In many cases (particularly
      performance-sensitive cases) the callee will be in assembler anyway,
      and need not use the compiler's calling convention.
      
      Standard calling convention is:
      	 arguments	    return	scratch
      x86-32	 eax edx ecx	    eax		?
      x86-64	 rdi rsi rdx rcx    rax		r8 r9 r10 r11
      
      The thunk preserves all argument and scratch registers.  The return
      register is not preserved, and is available as a scratch register for
      unwrapped callee code (and of course the return value).
      
      Wrapped function pointers are themselves wrapped in a struct
      paravirt_callee_save structure, in order to get some warning from the
      compiler when functions with mismatched calling conventions are used.
      
      The most common paravirt ops, both statically and dynamically, are
      interrupt enable/disable/save/restore, so handle them first.  This is
      particularly easy since their calls are handled specially anyway.
      
      XXX Deal with VMI.  What's their calling convention?
      Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
      ecb93d1c
  7. 30 1月, 2009 1 次提交
  8. 13 12月, 2008 1 次提交
  9. 12 11月, 2008 1 次提交
  10. 31 10月, 2008 2 次提交
  11. 16 10月, 2008 1 次提交
    • Y
      x86: make 32bit support per_cpu vector · 497c9a19
      Yinghai Lu 提交于
      so we can merge io_apic_32.c and io_apic_64.c
      
      v2: Use cpu_online_map as target cpus for bigsmp, just like 64-bit is doing.
      
      Also remove some unused TARGET_CPUS macro.
      
      v3: need to check if desc is null in smp_irq_move_cleanup
      
      also migration needs to reset vector too, so copy __target_IO_APIC_irq
      from 64bit.
      
      (the duplication will go away once the two files are unified.)
      Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      497c9a19
  12. 29 7月, 2008 1 次提交
  13. 20 7月, 2008 1 次提交
  14. 19 7月, 2008 1 次提交
  15. 18 7月, 2008 1 次提交
    • M
      x86: APIC: remove apic_write_around(); use alternatives · 593f4a78
      Maciej W. Rozycki 提交于
      Use alternatives to select the workaround for the 11AP Pentium erratum
      for the affected steppings on the fly rather than build time.  Remove the
      X86_GOOD_APIC configuration option and replace all the calls to
      apic_write_around() with plain apic_write(), protecting accesses to the
      ESR as appropriate due to the 3AP Pentium erratum.  Remove
      apic_read_around() and all its invocations altogether as not needed.
      Remove apic_write_atomic() and all its implementing backends.  The use of
      ASM_OUTPUT2() is not strictly needed for input constraints, but I have
      used it for readability's sake.
      
      I had the feeling no one else was brave enough to do it, so I went ahead
      and here it is.  Verified by checking the generated assembly and tested
      with both a 32-bit and a 64-bit configuration, also with the 11AP
      "feature" forced on and verified with gdb on /proc/kcore to work as
      expected (as an 11AP machines are quite hard to get hands on these days).
      Some script complained about the use of "volatile", but apic_write() needs
      it for the same reason and is effectively a replacement for writel(), so I
      have disregarded it.
      
      I am not sure what the policy wrt defconfig files is, they are generated
      and there is risk of a conflict resulting from an unrelated change, so I
      have left changes to them out.  The option will get removed from them at
      the next run.
      
      Some testing with machines other than mine will be needed to avoid some
      stupid mistake, but despite its volume, the change is not really that
      intrusive, so I am fairly confident that because it works for me, it will
      everywhere.
      Signed-off-by: NMaciej W. Rozycki <macro@linux-mips.org>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      593f4a78
  16. 12 7月, 2008 1 次提交
  17. 09 7月, 2008 1 次提交
  18. 08 7月, 2008 1 次提交
  19. 31 5月, 2008 1 次提交
  20. 30 5月, 2008 1 次提交
  21. 17 4月, 2008 1 次提交
  22. 28 3月, 2008 1 次提交
  23. 11 3月, 2008 2 次提交
    • R
      lguest: Revert 1ce70c4f, fix real problem. · 4357bd94
      Rusty Russell 提交于
      Ahmed managed to crash the Host in release_pgd(), which cannot be a Guest
      bug, and indeed it wasn't.
      
      The bug was that handing a 0 as the address of the toplevel page table
      being manipulated can cause the lookup code in find_pgdir() to return
      an uninitialized cache entry (we shadow up to 4 top level page tables
      for each Guest).
      
      Commit 37cc8d7f introduced this
      behaviour in the Guest, uncovering the bug.
      
      The patch which he submitted (which removed the /4 from the index
      calculation) simply ensured that these high-indexed entries hit the
      early exit path of guest_set_pmd().  But you get lots of segfaults in
      guest userspace as the PMDs aren't being updated.
      Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
      4357bd94
    • R
      lguest: Sanitize the lguest clock. · 3fabc55f
      Rusty Russell 提交于
      Now the TSC code handles a zero return from calculate_cpu_khz(),
      lguest can simply pass through the value it gets from the Host: if
      non-zero, all the normal TSC code applies.
      
      Otherwise (or if the Host really doesn't support TSC), the clocksource
      code will fall back to the slower but reasonable lguest clock.
      Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
      3fabc55f
  24. 26 2月, 2008 2 次提交
    • A
      x86/lguest: fix pgdir pmd index calculation · 1ce70c4f
      Ahmed S. Darwish 提交于
      Hi all,
      
      Beginning from commits close to v2.6.25-rc2, running lguest always oopses
      the host kernel. Oops is at [1].
      
      Bisection led to the following commit:
      
      commit 37cc8d7f
      
          x86/early_ioremap: don't assume we're using swapper_pg_dir
      
          At the early stages of boot, before the kernel pagetable has been
          fully initialized, a Xen kernel will still be running off the
          Xen-provided pagetables rather than swapper_pg_dir[].  Therefore,
          readback cr3 to determine the base of the pagetable rather than
          assuming swapper_pg_dir[].
      
       static inline pmd_t * __init early_ioremap_pmd(unsigned long addr)
       {
      -	pgd_t *pgd = &swapper_pg_dir[pgd_index(addr)];
      +	/* Don't assume we're using swapper_pg_dir at this point */
      +	pgd_t *base = __va(read_cr3());
      +	pgd_t *pgd = &base[pgd_index(addr)];
       	pud_t *pud = pud_offset(pgd, addr);
       	pmd_t *pmd = pmd_offset(pud, addr);
      
      Trying to analyze the problem, it seems on the guest side of lguest,
      %cr3 has a different value from &swapper_pg-dir (which
      is AFAIK fine on a pravirt guest):
      
      Putting some debugging messages in early_ioremap_pmd:
      
      /* Appears 3 times */
      [    0.000000] ***************************
      [    0.000000] __va(%cr3) = c0000000, &swapper_pg_dir = c02cc000
      [    0.000000] ***************************
      
      After 8 hours of debugging and staring on lguest code, I noticed something
      strange in paravirt_ops->set_pmd hypercall invocation:
      
      static void lguest_set_pmd(pmd_t *pmdp, pmd_t pmdval)
      {
      	*pmdp = pmdval;
      	lazy_hcall(LHCALL_SET_PMD, __pa(pmdp)&PAGE_MASK,
      		   (__pa(pmdp)&(PAGE_SIZE-1))/4, 0);
      }
      
      The first hcall parameter is global pgdir which looks fine. The second
      parameter is the pmd index in the pgdir which is suspectful.
      
      AFAIK, calculating the index of pmd does not need a divisoin over four.
      Removing the division made lguest work fine again . Patch is at [2].
      
      I am not sure why the division over four existed in the first place. It
      seems bogus, maybe the Xen patch just made the problem appear ?
      
      [2]: The patch:
      
      [PATCH] lguest: fix pgdir pmd index cacluation
      
      Remove an error in index calculation which leads to removing
      a not existing shadow page table (leading to a Null dereference).
      Signed-off-by: NAhmed S. Darwish <darwish.07@gmail.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      1ce70c4f
    • H
      lguest: include function prototypes · cbc34973
      Harvey Harrison 提交于
      Added a declaration to asm-x86/lguest.h and moved the extern arrays there
      as well.  As an alternative to including asm/lguest.h directly, an
      include could be put in linux/lguest.h
      Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
      Cc: "rusty@rustcorp.com.au" <rusty@rustcorp.com.au>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      cbc34973
  25. 30 1月, 2008 7 次提交
  26. 05 11月, 2007 2 次提交
  27. 25 10月, 2007 3 次提交