kernel.git/arch/powerpc/kernel/exceptions-64s.S, branch linux-3.17.y

powerpc: Fix "attempt to move .org backwards" error

2014-08-13T05:13:25Z

Once again, we see arch/powerpc/kernel/exceptions-64s.S: Assembler messages: arch/powerpc/kernel/exceptions-64s.S:865: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:866: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:890: Error: attempt to move .org backwards when compiling ppc:allmodconfig. This time the problem has been caused by to commit 0869b6fd209bda ("powerpc/book3s: Add basic infrastructure to handle HMI in Linux"), which adds functions hmi_exception_early and hmi_exception_after_realmode into a critical (size-limited) code area, even though that does not appear to be necessary. Move those functions to a non-critical area of the file. Signed-off-by: Guenter Roeck Signed-off-by: Benjamin Herrenschmidt

powerpc/book3s: Add basic infrastructure to handle HMI in Linux.

2014-08-05T06:33:48Z

Handle Hypervisor Maintenance Interrupt (HMI) in Linux. This patch implements basic infrastructure to handle HMI in Linux host. The design is to invoke opal handle hmi in real mode for recovery and set irq_pending when we hit HMI. During check_irq_replay pull opal hmi event and print hmi info on console. Signed-off-by: Mahesh Salgaonkar Signed-off-by: Benjamin Herrenschmidt

powerpc: Remove misleading DISABLE_INTS

2014-07-28T04:11:24Z

DISABLE_INTS has a long and storied history, but for some time now it has not actually disabled interrupts. For the open-coded exception handlers, just stop using it, instead call RECONCILE_IRQ_STATE directly. This has the benefit of removing a level of indirection, and making it clear that r10 & r11 are used at that point. For the addition case we still need a macro, so rename it to clarify what it actually does. Signed-off-by: Michael Ellerman Signed-off-by: Benjamin Herrenschmidt

powerpc: Move bad_stack() below the fwnmi_data_area

2014-07-28T04:11:22Z

At the moment the allmodconfig build is failing because we run out of space between altivec_assist() at 0x5700 and the fwnmi_data_area at 0x7000. Fixing it permanently will take some more work, but a quick fix is to move bad_stack() below the fwnmi_data_area. That gives us just enough room with everything enabled. bad_stack() is called from the common exception handlers, but it's a non-conditional branch, so we have plenty of scope to move it further way. Signed-off-by: Michael Ellerman Signed-off-by: Benjamin Herrenschmidt

powerpc: Remove STAB code

2014-07-28T04:10:22Z

Old cpus didn't have a Segment Lookaside Buffer (SLB), instead they had a Segment Table (STAB). Now that we've dropped support for those cpus, we can remove the STAB support entirely. Signed-off-by: Michael Ellerman Signed-off-by: Benjamin Herrenschmidt

powerpc/book3s: Fix some ABIv2 issues in machine check code

2014-06-11T23:41:33Z

Commit 2749a2f26a7c (powerpc/book3s: Fix machine check handling for unhandled errors) introduced a few ABIv2 issues. We can maintain ABIv1 and ABIv2 compatibility by branching to the function rather than the dot symbol. Fixes: 2749a2f26a7c ("powerpc/book3s: Fix machine check handling for unhandled errors") Signed-off-by: Anton Blanchard Signed-off-by: Benjamin Herrenschmidt

powerpc/book3s: Add stack overflow check in machine check handler.

2014-06-11T09:15:13Z

Currently machine check handler does not check for stack overflow for nested machine check. If we hit another MCE while inside the machine check handler repeatedly from same address then we get into risk of stack overflow which can cause huge memory corruption. This patch limits the nested MCE level to 4 and panic when we cross level 4. Signed-off-by: Mahesh Salgaonkar Signed-off-by: Benjamin Herrenschmidt

powerpc/book3s: Fix machine check handling for unhandled errors

2014-06-11T09:15:13Z

Current code does not check for unhandled/unrecovered errors and return from interrupt if it is recoverable exception which in-turn triggers same machine check exception in a loop causing hypervisor to be unresponsive. This patch fixes this situation and forces hypervisor to panic for unhandled/unrecovered errors. This patch also fixes another issue where unrecoverable_exception routine was called in real mode in case of unrecoverable exception (MSR_RI = 0). This causes another exception vector 0x300 (data access) during system crash leading to confusion while debugging cause of the system crash. Also turn ME bit off while going down, so that when another MCE is hit during panic path, system will checkstop and hypervisor will get restarted cleanly by SP. With the above fixes we now throw correct console messages (see below) while crashing the system in case of unhandled/unrecoverable machine checks. -------------- Severe Machine check interrupt [[Not recovered] Initiator: CPU Error type: UE [Instruction fetch] Effective address: 0000000030002864 Oops: Machine check, sig: 7 [#1] SMP NR_CPUS=2048 NUMA PowerNV Modules linked in: bork(O) bridge stp llc kvm [last unloaded: bork] CPU: 36 PID: 55162 Comm: bash Tainted: G O 3.14.0mce #1 task: c000002d72d022d0 ti: c000000007ec0000 task.ti: c000002d72de4000 NIP: 0000000030002864 LR: 00000000300151a4 CTR: 000000003001518c REGS: c000000007ec3d80 TRAP: 0200 Tainted: G O (3.14.0mce) MSR: 9000000000041002 CR: 28222848 XER: 20000000 CFAR: 0000000030002838 DAR: d0000000004d0000 DSISR: 00000000 SOFTE: 1 GPR00: 000000003001512c 0000000031f92cb0 0000000030078af0 0000000030002864 GPR04: d0000000004d0000 0000000000000000 0000000030002864 ffffffffffffffc9 GPR08: 0000000000000024 0000000030008af0 000000000000002c c00000000150e728 GPR12: 9000000000041002 0000000031f90000 0000000010142550 0000000040000000 GPR16: 0000000010143cdc 0000000000000000 00000000101306fc 00000000101424dc GPR20: 00000000101424e0 000000001013c6f0 0000000000000000 0000000000000000 GPR24: 0000000010143ce0 00000000100f6440 c000002d72de7e00 c000002d72860250 GPR28: c000002d72860240 c000002d72ac0038 0000000000000008 0000000000040000 NIP [0000000030002864] 0x30002864 LR [00000000300151a4] 0x300151a4 Call Trace: Instruction dump: XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX ---[ end trace 7285f0beac1e29d3 ]--- Sending IPI to other CPUs IPI complete OPAL V3 detected ! -------------- Signed-off-by: Mahesh Salgaonkar Signed-off-by: Benjamin Herrenschmidt

powerpc: Remove dot symbol usage in exception macros

2014-04-23T00:05:19Z

STD_EXCEPTION_COMMON, STD_EXCEPTION_COMMON_ASYNC and MASKABLE_EXCEPTION branch to the handler, so we can remove the explicit dot symbol and binutils will do the right thing. Signed-off-by: Anton Blanchard

powerpc: Remove some unnecessary uses of _GLOBAL() and _STATIC()

2014-04-23T00:05:18Z

There is no need to create a function descriptor for functions called locally out of assembly. Signed-off-by: Anton Blanchard