Skip to content

cloud-kernel
cloud-kernel

openanolis / cloud-kernel
1 年多 前同步成功

通知 160
Star 36
Fork 7
cloud-kernel
cloud-kernel
切换分支/标签
  1. 22 6月, 2015 6 次提交
    • V
      ARCv2: STAR 9000814690: Really Re-enable interrupts to avoid deadlocks · 4de0e528
      由 Vineet Gupta 提交于 
      The issue was, on HS when interrupt is taken, IRQ_ACT is set and that is
NOT cleared unless we do RTIE (or manually clear it). Linux interrupt
handling has top and bottom halves. Latter lead to softirqs (which can
reschedule) AND expect interrupts to be REALLY re-enabled which was NOT
happening for us since we only SETI, dont clear IRQ_ACT

So we can have a state when both cores have taken interrupt (IRQ_ACT set),
get rescheduled, both send IPI and wait in CSD lock which will never be
cleared as cores can't take the pending IPI IRQ due to existing IRQ_ACT
set.

So local_irq_enable() now drops the IRQ_ACT.act bit to re-enable IRQs.
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
      4de0e528
    • V
      ARCv2: STAR 9000808988: signals involving Delay Slot · 0d7b8855
      由 Vineet Gupta 提交于 
      Reported by Anton as LTP:munmap01 failing with Illegal Instruction
Exception.

   --------------------->8--------------------------------------
   mmap2(NULL, 24576, PROT_READ|PROT_WRITE, MAP_SHARED, 3, 0) = 0x200d2000
   munmap(0x200d2000, 24576)               = 0
   --- SIGSEGV {si_signo=SIGSEGV, si_code=SEGV_MAPERR, si_addr=0x200d2000}
   ---
   potentially unexpected fatal signal 4.
   Path: /munmap01
   CPU: 0 PID: 61 Comm: munmap01 Not tainted 3.13.0-g5d5c46d9a556 #8
   task: 9f1a8000 ti: 9f154000 task.ti: 9f154000

   [ECR   ]: 0x00020100 => Illegal Insn
   [EFA   ]: 0x0001354c
   [BLINK ]: 0x200515d4
   [ERET  ]: 0x1354c
       @off 0x1354c in [/munmap01]
       VMA: 0x00010000 to 0x00018000
   [STAT32]: 0x800802c0
   ...
   --------------------->8--------------------------------------

The issue was
1. munmap01 accessed unmapped memory (on purpose) with signal handler
   installed for SIGSEGV

2. The faulting instruction happened to be in Delay Slot
   00011864 <main>:
      11908:	bl.d       13284 <tst_resm>
      1190c:	stb        r16,[r2]

3. kernel sets up the reg file for signal handler and correctly clears
   the DE bit in pt_regs->status32 placeholder

4. However RESTORE_CALLEE_SAVED_USER macro is not adjusted for ARCv2,
   and it over-writes the above with orig/stale value of status32

5. After RTIE, userspace signal handler executes a non branch
   instruction with DE bit set, triggering Illegal Instruction Exception.
Reported-by: NAnton Kolesov <akolesov@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
      0d7b8855
    • V
      ARCv2: STAR 9000793984: Handle return from intr to Delay Slot · 4255b07f
      由 Vineet Gupta 提交于 
      Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
      4255b07f
    • V
      ARCv2: Support for ARCv2 ISA and HS38x cores · 1f6ccfff
      由 Vineet Gupta 提交于 
      The notable features are:
    - SMP configurations of upto 4 cores with coherency
    - Optional L2 Cache and IO-Coherency
    - Revised Interrupt Architecture (multiple priorites, reg banks,
        auto stack switch, auto regfile save/restore)
    - MMUv4 (PIPT dcache, Huge Pages)
    - Instructions for
	* 64bit load/store: LDD, STD
	* Hardware assisted divide/remainder: DIV, REM
	* Function prologue/epilogue: ENTER_S, LEAVE_S
	* IRQ enable/disable: CLRI, SETI
	* pop count: FFS, FLS
	* SETcc, BMSKN, XBFU...
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
      1f6ccfff
    • V
      ARCv2: [intc] HS38 core interrupt controller · 820970a5
      由 Vineet Gupta 提交于 
      Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
      820970a5
    • V
      ARC: uncached base is hard constant for ARC, don't save it · 10d11e58
      由 Vineet Gupta 提交于 
      ioremap already uses the hard define, just make sure BCR value matches
that
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
      10d11e58
  3. 19 6月, 2015 34 次提交