linux-stable/arch/powerpc
Nicholas Piggin 3e607dc4df powerpc/64s: fix program check interrupt emergency stack path
Emergency stack path was jumping into a 3: label inside the
__GEN_COMMON_BODY macro for the normal path after it had finished,
rather than jumping over it. By a small miracle this is the correct
place to build up a new interrupt frame with the existing stack
pointer, so things basically worked okay with an added weird looking
700 trap frame on top (which had the wrong ->nip so it didn't decode
bug messages either).

Fix this by avoiding using numeric labels when jumping over non-trivial
macros.

Before:

 LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA PowerNV
 Modules linked in:
 CPU: 0 PID: 88 Comm: sh Not tainted 5.15.0-rc2-00034-ge057cdade6e5 #2637
 NIP:  7265677368657265 LR: c00000000006c0c8 CTR: c0000000000097f0
 REGS: c0000000fffb3a50 TRAP: 0700   Not tainted
 MSR:  9000000000021031 <SF,HV,ME,IR,DR,LE>  CR: 00000700  XER: 20040000
 CFAR: c0000000000098b0 IRQMASK: 0
 GPR00: c00000000006c964 c0000000fffb3cf0 c000000001513800 0000000000000000
 GPR04: 0000000048ab0778 0000000042000000 0000000000000000 0000000000001299
 GPR08: 000001e447c718ec 0000000022424282 0000000000002710 c00000000006bee8
 GPR12: 9000000000009033 c0000000016b0000 00000000000000b0 0000000000000001
 GPR16: 0000000000000000 0000000000000002 0000000000000000 0000000000000ff8
 GPR20: 0000000000001fff 0000000000000007 0000000000000080 00007fff89d90158
 GPR24: 0000000002000000 0000000002000000 0000000000000255 0000000000000300
 GPR28: c000000001270000 0000000042000000 0000000048ab0778 c000000080647e80
 NIP [7265677368657265] 0x7265677368657265
 LR [c00000000006c0c8] ___do_page_fault+0x3f8/0xb10
 Call Trace:
 [c0000000fffb3cf0] [c00000000000bdac] soft_nmi_common+0x13c/0x1d0 (unreliable)
 --- interrupt: 700 at decrementer_common_virt+0xb8/0x230
 NIP:  c0000000000098b8 LR: c00000000006c0c8 CTR: c0000000000097f0
 REGS: c0000000fffb3d60 TRAP: 0700   Not tainted
 MSR:  9000000000021031 <SF,HV,ME,IR,DR,LE>  CR: 22424282  XER: 20040000
 CFAR: c0000000000098b0 IRQMASK: 0
 GPR00: c00000000006c964 0000000000002400 c000000001513800 0000000000000000
 GPR04: 0000000048ab0778 0000000042000000 0000000000000000 0000000000001299
 GPR08: 000001e447c718ec 0000000022424282 0000000000002710 c00000000006bee8
 GPR12: 9000000000009033 c0000000016b0000 00000000000000b0 0000000000000001
 GPR16: 0000000000000000 0000000000000002 0000000000000000 0000000000000ff8
 GPR20: 0000000000001fff 0000000000000007 0000000000000080 00007fff89d90158
 GPR24: 0000000002000000 0000000002000000 0000000000000255 0000000000000300
 GPR28: c000000001270000 0000000042000000 0000000048ab0778 c000000080647e80
 NIP [c0000000000098b8] decrementer_common_virt+0xb8/0x230
 LR [c00000000006c0c8] ___do_page_fault+0x3f8/0xb10
 --- interrupt: 700
 Instruction dump:
 XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
 XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
 ---[ end trace 6d28218e0cc3c949 ]---

After:

 ------------[ cut here ]------------
 kernel BUG at arch/powerpc/kernel/exceptions-64s.S:491!
 Oops: Exception in kernel mode, sig: 5 [#1]
 LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA PowerNV
 Modules linked in:
 CPU: 0 PID: 88 Comm: login Not tainted 5.15.0-rc2-00034-ge057cdade6e5-dirty #2638
 NIP:  c0000000000098b8 LR: c00000000006bf04 CTR: c0000000000097f0
 REGS: c0000000fffb3d60 TRAP: 0700   Not tainted
 MSR:  9000000000021031 <SF,HV,ME,IR,DR,LE>  CR: 24482227  XER: 00040000
 CFAR: c0000000000098b0 IRQMASK: 0
 GPR00: c00000000006bf04 0000000000002400 c000000001513800 c000000001271868
 GPR04: 00000000100f0d29 0000000042000000 0000000000000007 0000000000000009
 GPR08: 00000000100f0d29 0000000024482227 0000000000002710 c000000000181b3c
 GPR12: 9000000000009033 c0000000016b0000 00000000100f0d29 c000000005b22f00
 GPR16: 00000000ffff0000 0000000000000001 0000000000000009 00000000100eed90
 GPR20: 00000000100eed90 0000000010000000 000000001000a49c 00000000100f1430
 GPR24: c000000001271868 0000000002000000 0000000000000215 0000000000000300
 GPR28: c000000001271800 0000000042000000 00000000100f0d29 c000000080647860
 NIP [c0000000000098b8] decrementer_common_virt+0xb8/0x230
 LR [c00000000006bf04] ___do_page_fault+0x234/0xb10
 Call Trace:
 Instruction dump:
 4182000c 39400001 48000008 894d0932 714a0001 39400008 408225fc 718a4000
 7c2a0b78 3821fcf0 41c20008 e82d0910 <0981fcf0> f92101a0 f9610170 f9810178
 ---[ end trace a5dbd1f5ea4ccc51 ]---

Fixes: 0a882e2846 ("powerpc/64s/exception: remove bad stack branch")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211004145642.1331214-2-npiggin@gmail.com
2021-10-07 19:54:54 +11:00
..
boot powerpc/boot: Fix build failure since GCC 4.9 removal 2021-09-14 08:33:32 -07:00
configs powerpc/configs/microwatt: Enable options for systemd 2021-08-27 00:56:53 +10:00
crypto crypto: powepc/sha1 - remove unneeded semicolon 2021-03-07 15:13:14 +11:00
include powerpc/security: Add a helper to query stf_barrier type 2021-10-07 19:52:58 +11:00
kernel powerpc/64s: fix program check interrupt emergency stack path 2021-10-07 19:54:54 +11:00
kexec powerpc updates for 5.15 2021-09-03 11:22:50 -07:00
kvm KVM: PPC: Book3S HV: Tolerate treclaim. in fake-suspend mode changing registers 2021-09-13 22:34:12 +10:00
lib powerpc/lib: Add helper to check if offset is within conditional branch range 2021-10-07 18:52:33 +11:00
math-emu powerpc/64s: avoid reloading (H)SRR registers if they are still valid 2021-06-25 00:06:55 +10:00
mm Merge branch 'akpm' (patches from Andrew) 2021-09-08 12:55:35 -07:00
net powerpc/bpf ppc32: Fix BPF_SUB when imm == 0x80000000 2021-10-07 19:52:59 +11:00
perf powerpc/perf: Fix the check for SIAR value 2021-08-25 22:38:19 +10:00
platforms Merge branch 'akpm' (patches from Andrew) 2021-09-08 12:55:35 -07:00
purgatory powerpc/kexec: Don't use .machine ppc64 in trampoline_64.S 2021-04-08 21:17:43 +10:00
sysdev powerpc/xics: Set the IRQ chip data for the ICS native backend 2021-09-15 22:05:53 +10:00
tools powerpc/head_check: Fix shellcheck errors 2021-08-17 22:52:02 +10:00
xmon powerpc: Refactor verification of MSR_RI 2021-08-26 21:21:07 +10:00
Kbuild
Kconfig Tracing updates for 5.15: 2021-09-05 11:50:41 -07:00
Kconfig.debug powerpc/ptdump: Convert powerpc to GENERIC_PTDUMP 2021-08-25 13:35:48 +10:00
Makefile powerpc: Add "-z notext" flag to disable diagnostic 2021-08-15 13:49:39 +10:00
Makefile.postlink