- 01 Apr, 2020 24 commits
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Nicholas Piggin authored
The soft NMI handler does not reconcile interrupt state, so it should not return via the normal ret_from_except path. Return like other NMIs, using the EXCEPTION_RESTORE_REGS macro. This becomes important when the scv interrupt is implemented, which must handle soft-masked interrupts that have r13 set to something other than the PACA -- returning to kernel in this case must restore r13. Signed-off-by:
Nicholas Piggin <npiggin@gmail.com> Signed-off-by:
Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225173541.1549955-23-npiggin@gmail.com
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Nicholas Piggin authored
This adds IRQ_HARD_DIS to irq_happened. Although it doesn't seem to matter much because we're not allowed to enable irqs in an NMI handler, the soft-irq debugging code is becoming more strict about ensuring IRQ_HARD_DIS is in sync with MSR[EE], this may help avoid asserts or other issues. Add a comment explaining why MCE does not have this. Early machine check is generally much smaller and more contained code which will explode if you look at it wrong anyway as it runs in real mode, though there's an argument that we should do similar reconciling for the MCE as well. Signed-off-by:
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Nicholas Piggin authored
Apart from SRESET, MCE, and syscall (hcall variant), the SRR type interrupts are not escalated to hypervisor mode, so are delivered to the OS. When running PR KVM, the OS is the hypervisor, and the guest runs with MSR[PR]=1 (ie. usermode), so these interrupts must test if a guest was running when interrupted. These tests are required at the real-mode entry points because the PR KVM host runs with LPCR[AIL]=0. In HV KVM and nested HV KVM, the guest always receives these interrupts, so there is no need for the host to make this test. So remove the tests if PR KVM is not configured. Signed-off-by:
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Nicholas Piggin authored
A few of the non-standard handlers are left uncommented. Some more description could be added to some. Signed-off-by:
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Nicholas Piggin authored
Remove more magic numbers and replace with nicely named bools. Signed-off-by:
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Nicholas Piggin authored
The reduction in interrupt entry size allows some handlers to be re-inlined. Signed-off-by:
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Nicholas Piggin authored
The hdec interrupt handler is reported to sometimes fire in Linux if KVM leaves it pending after a guest exists. This is harmless, so there is a no-op handler for it. The interrupt handler currently uses the regular kernel stack. Change this to avoid touching the stack entirely. This should be the last place where the regular Linux stack can be accessed with asynchronous interrupts (including PMI) soft-masked. It might be possible to take advantage of this invariant, e.g., to context switch the kernel stack SLB entry without clearing MSR[EE]. Signed-off-by:
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Nicholas Piggin authored
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Nicholas Piggin authored
These are used infrequently enough they don't provide much help, so inline them. Signed-off-by:
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Nicholas Piggin authored
Replace IEARLY=1 and IEARLY=2 with IBRANCH_COMMON, which controls if the entry code branches to a common handler; and IREALMODE_COMMON, which controls whether the common handler should remain in real mode. These special cases no longer avoid loading the SRR registers, there is no point as most of them load the registers immediately anyway. Signed-off-by:
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Nicholas Piggin authored
This allows more code to be moved out of unrelocated regions. The system call KVMTEST is changed to be open-coded and remain in the tramp area to avoid having to move it to entry_64.S. The custom nature of the system call entry code means the hcall case can be made more streamlined than regular interrupt handlers. mpe: Incorporate fix from Nick: Moving KVM test to the common entry code missed the case of HMI and MCE, which do not do __GEN_COMMON_ENTRY (because they don't want to switch to virt mode). This means a MCE or HMI exception that is taken while KVM is running a guest context will not be switched out of that context, and KVM won't be notified. Found by running sigfuz in guest with patched host on POWER9 DD2.3, which causes some TM related HMI interrupts (which are expected and supposed to be handled by KVM). This fix adds a __GEN_REALMODE_COMMON_ENTRY for those handlers to add the KVM test. This makes them look a little more like other handlers that all use __GEN_COMMON_ENTRY. Signed-off-by:
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Nicholas Piggin authored
As well as moving code out of the unrelocated vectors, this allows the masked handlers to be moved to common code, and allows the soft_nmi handler to be generated more like a regular handler. Signed-off-by:
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Nicholas Piggin authored
The real mode interrupt entry points currently use rfid to branch to the common handler in virtual mode. This is a significant amount of code, and forces other code (notably the KVM test) to live in the real mode handler. In the interest of minimising the amount of code that runs unrelocated move the switch to virt mode into the common code, and do it with mtmsrd, which avoids clobbering SRRs (although the post-KVMTEST performance of real-mode interrupt handlers is not a big concern these days). This requires CTR to always be saved (real-mode needs to reach 0xc...) but that's not a huge impact these days. It could be optimized away in future. mpe: Incorporate fix from Nick: It's possible for interrupts to be replayed when TM is enabled and suspended, for example rt_sigreturn, where the mtmsrd MSR_KERNEL in the real-mode entry point to the common handler causes a TM Bad Thing exception (due to attempting to clear suspended). The fix for this is to have replay interrupts go to the _virt entry point and skip the mtmsrd, which matches what happens before this patch. Signed-off-by:
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Nicholas Piggin authored
Rather than using DAR=2 to select the i-side registers, add an explicit option. Signed-off-by:
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Nicholas Piggin authored
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Nicholas Piggin authored
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Nicholas Piggin authored
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Nicholas Piggin authored
Aside from label names and BUG line numbers, the generated code change is an additional HMI KVM handler added for the "late" KVM handler, because early and late HMI generation is achieved by defining two different interrupt types. Signed-off-by:
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Nicholas Piggin authored
These don't provide a large amount of code sharing. Removing them makes code easier to shuffle around. For example, some of the common instructions will be moved into the common code gen macro. No generated code change. Signed-off-by:
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Nicholas Piggin authored
No generated code change. Signed-off-by:
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Nicholas Piggin authored
No generated code change. Signed-off-by:
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Nicholas Piggin authored
The code generation macro arguments are difficult to read, and defaults can't easily be used. This introduces a block where parameters can be set for interrupt handler code generation by the subsequent macros, and adds the first generation macro for interrupt entry. One interrupt handler is converted to the new macros to demonstrate the change, the rest will be coverted all at once. No generated code change. Signed-off-by:
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Nicholas Piggin authored
Before: WARNING: CPU: 0 PID: 494 at arch/powerpc/kernel/irq.c:343 CPU: 0 PID: 494 Comm: a Tainted: G W NIP: c00000000001ed2c LR: c000000000d13190 CTR: c00000000003f910 REGS: c0000001fffd3870 TRAP: 0700 Tainted: G W MSR: 8000000000021003 <SF,ME,RI,LE> CR: 28000488 XER: 00000000 CFAR: c00000000001ec90 IRQMASK: 0 GPR00: c000000000aeb12c c0000001fffd3b00 c0000000012ba300 0000000000000000 GPR04: 0000000000000000 0000000000000000 000000010bd207c8 6b00696e74657272 GPR08: 0000000000000000 0000000000000000 0000000000000000 efbeadde00000000 GPR12: 0000000000000000 c0000000014a0000 0000000000000000 0000000000000000 GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR24: 0000000000000000 0000000000000000 0000000000000000 000000010bd207bc GPR28: 0000000000000000 c00000000148a898 0000000000000000 c0000001ffff3f50 NIP [c00000000001ed2c] arch_local_irq_restore.part.0+0xac/0x100 LR [c000000000d13190] _raw_spin_unlock_irqrestore+0x50/0xc0 Call Trace: Instruction dump: 60000000 7d2000a6 71298000 41820068 39200002 7d210164 4bffff9c 60000000 60000000 7d2000a6 71298000 4c820020 <0fe00000> 4e800020 60000000 60000000 After: WARNING: CPU: 0 PID: 499 at arch/powerpc/kernel/irq.c:343 CPU: 0 PID: 499 Comm: a Not tainted NIP: c00000000001ed2c LR: c000000000d13210 CTR: c00000000003f980 REGS: c0000001fffd3870 TRAP: 0700 Not tainted MSR: 8000000000021003 <SF,ME,RI,LE> CR: 28000488 XER: 00000000 CFAR: c00000000001ec90 IRQMASK: 0 GPR00: c000000000aeb1ac c0000001fffd3b00 c0000000012ba300 0000000000000000 GPR04: 0000000000000000 0000000000000000 00000001347607c8 6b00696e74657272 GPR08: 0000000000000000 0000000000000000 0000000000000000 efbeadde00000000 GPR12: 0000000000000000 c0000000014a0000 0000000000000000 0000000000000000 GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR24: 0000000000000000 0000000000000000 0000000000000000 00000001347607bc GPR28: 0000000000000000 c00000000148a898 0000000000000000 c0000001ffff3f50 NIP [c00000000001ed2c] arch_local_irq_restore.part.0+0xac/0x100 LR [c000000000d13210] _raw_spin_unlock_irqrestore+0x50/0xc0 Call Trace: [c0000001fffd3b20] [c000000000aeb1ac] of_find_property+0x6c/0x90 [c0000001fffd3b70] [c000000000aeb1f0] of_get_property+0x20/0x40 [c0000001fffd3b90] [c000000000042cdc] rtas_token+0x3c/0x70 [c0000001fffd3bb0] [c0000000000dc318] fwnmi_release_errinfo+0x28/0x70 [c0000001fffd3c10] [c0000000000dcd8c] pseries_machine_check_realmode+0x1dc/0x540 [c0000001fffd3cd0] [c00000000003fe04] machine_check_early+0x54/0x70 [c0000001fffd3d00] [c000000000008384] machine_check_early_common+0x134/0x1f0 --- interrupt: 200 at 0x1347607c8 LR = 0x7fffafbd8328 Instruction dump: 60000000 7d2000a6 71298000 41820068 39200002 7d210164 4bffff9c 60000000 60000000 7d2000a6 71298000 4c820020 <0fe00000> 4e800020 60000000 60000000 Signed-off-by: -
Michael Ellerman authored
In restore_tm_sigcontexts() we take the trap value directly from the user sigcontext with no checking: err |= __get_user(regs->trap, &sc->gp_regs[PT_TRAP]); This means we can be in the kernel with an arbitrary regs->trap value. Although that's not immediately problematic, there is a risk we could trigger one of the uses of CHECK_FULL_REGS(): #define CHECK_FULL_REGS(regs) BUG_ON(regs->trap & 1) It can also cause us to unnecessarily save non-volatile GPRs again in save_nvgprs(), which shouldn't be problematic but is still wrong. It's also possible it could trick the syscall restart machinery, which relies on regs->trap not being == 0xc00 (see 9a81c16b ("powerpc: fix double syscall restarts")), though I haven't been able to make that happen. Finally it doesn't match the behaviour of the non-TM case, in restore_sigcontext() which zeroes regs->trap. So change restore_tm_sigcontexts() to zero regs->trap. This was discovered while testing Nick's upcoming rewrite of the syscall entry path. In that series the call to save_nvgprs() prior to signal handling (do_notify_resume()) is removed, which leaves the low-bit of regs->trap uncleared which can then trigger the FULL_REGS() WARNs in setup_tm_sigcontexts(). Fixes: 2b0a576d ("powerpc: Add new transactional memory state to the signal context") Cc: stable@vger.kernel.org # v3.9+ Signed-off-by:
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- 27 Mar, 2020 3 commits
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Aneesh Kumar K.V authored
As per ISA an isync is only needed on instruction cache block invalidate. Remove the same from dcache invalidate. Signed-off-by:
Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by:
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Fangrui Song authored
.globl sets the symbol binding to STB_GLOBAL while .weak sets the binding to STB_WEAK. GNU as let .weak override .globl since binutils-gdb 5ca547dc2399a0a5d9f20626d4bf5547c3ccfddd (1996). Clang integrated assembler let the last win but it may error in the future. Since it is a convention that only one binding directive is used, just delete .globl. Fixes: ee9d21b3 ("powerpc/boot: Ensure _zimage_start is a weak symbol") Signed-off-by:
Fangrui Song <maskray@google.com> Signed-off-by:
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Ganesh Goudar authored
memcpy_mcsafe has been implemented for power machines which is used by pmem infrastructure, so that an UE encountered during memcpy from pmem devices would not result in panic instead a right error code is returned. The implementation expects machine check handler to ignore the event and set nip to continue the execution from fixup code. Appropriate changes are already made to powernv machine check handler, make similar changes to pseries machine check handler to ignore the the event and set nip to continue execution at the fixup entry if we hit UE at an instruction with a fixup entry. while we are at it, have a common function which searches the exception table entry and updates nip with fixup address, and any future common changes can be made in this function that are valid for both architectures. powernv changes are made by commit 895e3dce ("powerpc/mce: Handle UE event for memcpy_mcsafe") Reviewed-by:
Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Reviewed-by:
Santosh S <santosh@fossix.org> Signed-off-by:
Ganesh Goudar <ganeshgr@linux.ibm.com> Signed-off-by:
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- 26 Mar, 2020 13 commits
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Michael Ellerman authored
We can avoid the #ifdef by using IS_ENABLED() in the existing condition check. Signed-off-by:
Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by:
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Michael Ellerman authored
We don't need the NULL check of np, the result is the same because the OF helpers cope with NULL, of_node_to_nid(NULL) == NUMA_NO_NODE (-1). Signed-off-by:
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Michael Ellerman authored
It's over 10 years since the last commit from Vitaly, so I suspect he's moved on to other things. Christophe has been the primary contributor to 8xx in the last several years, so anoint him as the maintainer. Remove the dead penguingppc.org link. Signed-off-by:
Christophe Leroy <christophe.leroy@c-s.fr> Link: https://lore.kernel.org/r/20200225092534.9587-1-mpe@ellerman.id.au
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Michael Ellerman authored
Scott said he was still maintaining this "sort of", so change the status to Odd Fixes. Kumar has long ago moved on to greener pastures. Remove the dead penguinppc.org link. Signed-off-by:
Scott Wood <oss@buserror.net> Link: https://lore.kernel.org/r/20200224233146.23734-8-mpe@ellerman.id.au
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Michael Ellerman authored
Ben is no longer actively maintaining the powermac code, but we know where to find him if something really needs attention. The www.penguinppc.org link is dead so remove it. Signed-off-by:
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Michael Ellerman authored
It's several years since the last commit from Anatolij, so mark MPC5XXX as "Odd Fixes" rather than "Maintained". Also the git link no longer works so remove it. Signed-off-by:
Anatolij Gustschin <agust@denx.de> Link: https://lore.kernel.org/r/20200224233146.23734-6-mpe@ellerman.id.au
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Michael Ellerman authored
This has been orphaned for ~7 years, remove it. Signed-off-by:
Grant Likely <grant.likely@arm.com> Link: https://lore.kernel.org/r/20200224233146.23734-5-mpe@ellerman.id.au
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Michael Ellerman authored
The 4xx platforms are no longer maintained. Signed-off-by:
Alistair Popple <alistair@popple.id.au> Link: https://lore.kernel.org/r/20200224233146.23734-4-mpe@ellerman.id.au
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Michael Ellerman authored
The PA SEMI entries have been orphaned for 3 ½ years, so fold them into the main POWERPC entry. The result of get_maintainer.pl is more or less unchanged. Signed-off-by:
Olof Johansson <olof@lixom.net> Link: https://lore.kernel.org/r/20200224233146.23734-3-mpe@ellerman.id.au
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Michael Ellerman authored
The wiki has moved, update the link. Signed-off-by:
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Michael Ellerman authored
A while back Paul pointed out I'd been maintaining the tree more or less solo for over five years, so perhaps it's time to update the MAINTAINERS entry. Ben & Paul still wrote most of the code, so keep them as Reviewers so they still get Cc'ed on things. But if you're wondering why your patch hasn't been merged that's my fault. Signed-off-by:
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Douglas Miller authored
The reason debuggers add an ASCII dump to other types of memory dumps is to give the user visual reference points in the case that ASCII strings are adjacent to other structures or element. For example, when examining the task_struct structure one can look for the comm[] string and use it to locate other important elements. ASCII strings do not have endianess, they exist in memory in the same order regardless of CPU endianess. ASCII strings are, by definition, human readable and so should be presented in a human readable format. For these reasons, the supplemental ASCII dump does not re-order the strings from memory to match the endianess of the corresponding 16, 32, or 64 bit words. That would make the ASCII dump much less useful. Signed-off-by:
Douglas Miller <dougmill@linux.vnet.ibm.com> Signed-off-by:
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Cédric Le Goater authored
As does XMON, the debugfs file /sys/kernel/debug/powerpc/xive exposes the XIVE internal state of the machine CPUs and interrupts. Available on the PowerNV and sPAPR platforms. Signed-off-by:
Cédric Le Goater <clg@kaod.org> [mpe: Make the debugfs file 0400] Signed-off-by:
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