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2020-04-01powerpc/64s/exception: Remove old INT_ENTRY macroNicholas Piggin
Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225173541.1549955-7-npiggin@gmail.com
2020-04-01powerpc/64s/exception: Move all interrupt handlers to new style code gen macrosNicholas Piggin
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: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225173541.1549955-6-npiggin@gmail.com
2020-04-01powerpc/64s/exception: Expand EXC_COMMON and EXC_COMMON_ASYNC macrosNicholas Piggin
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: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225173541.1549955-5-npiggin@gmail.com
2020-04-01powerpc/64s/exception: Add GEN_KVM macro that uses INT_DEFINE parametersNicholas Piggin
No generated code change. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225173541.1549955-4-npiggin@gmail.com
2020-04-01powerpc/64s/exception: Add GEN_COMMON macro that uses INT_DEFINE parametersNicholas Piggin
No generated code change. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225173541.1549955-3-npiggin@gmail.com
2020-04-01powerpc/64s/exception: Introduce INT_DEFINE parameter block for code generationNicholas Piggin
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: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225173541.1549955-2-npiggin@gmail.com
2020-04-01powerpc/64: mark emergency stacks valid to unwindNicholas Piggin
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: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200325104144.158362-1-npiggin@gmail.com
2020-04-01powerpc/64/tm: Don't let userspace set regs->trap via sigreturnMichael Ellerman
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 9a81c16b5275 ("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: 2b0a576d15e0 ("powerpc: Add new transactional memory state to the signal context") Cc: stable@vger.kernel.org # v3.9+ Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200401023836.3286664-1-mpe@ellerman.id.au
2020-03-27powerpc/pseries: Handle UE event for memcpy_mcsafeGanesh Goudar
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 895e3dceeb97 ("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: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200326184916.31172-1-ganeshgr@linux.ibm.com
2020-03-27powerpc/smp: Use IS_ENABLED() to avoid #ifdefMichael Ellerman
We can avoid the #ifdef by using IS_ENABLED() in the existing condition check. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200313112020.28235-2-mpe@ellerman.id.au
2020-03-27powerpc/smp: Drop superfluous NULL checkMichael Ellerman
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: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200313112020.28235-1-mpe@ellerman.id.au
2020-03-27powerpc: Prefer __section and __printf from compiler_attributes.hNick Desaulniers
Reported-by: Sedat Dilek <sedat.dilek@gmail.com> Suggested-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> [mpe: Drop changes to a/p/boot which doesn't use linux headers] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190812215052.71840-10-ndesaulniers@google.com
2020-03-25.gitignore: add SPDX License IdentifierMasahiro Yamada
Add SPDX License Identifier to all .gitignore files. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-25powerpc/prom_init: Remove leftover commentFabiano Rosas
The if statement that this comment referred to was removed in commit 11fdb309341c ("powerpc/prom_init: Remove support for OPAL v2"). Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200324182912.1048906-1-farosas@linux.ibm.com
2020-03-25powerpc/kprobes: Ignore traps that happened in real modeChristophe Leroy
When a program check exception happens while MMU translation is disabled, following Oops happens in kprobe_handler() in the following code: } else if (*addr != BREAKPOINT_INSTRUCTION) { BUG: Unable to handle kernel data access on read at 0x0000e268 Faulting instruction address: 0xc000ec34 Oops: Kernel access of bad area, sig: 11 [#1] BE PAGE_SIZE=16K PREEMPT CMPC885 Modules linked in: CPU: 0 PID: 429 Comm: cat Not tainted 5.6.0-rc1-s3k-dev-00824-g84195dc6c58a #3267 NIP: c000ec34 LR: c000ecd8 CTR: c019cab8 REGS: ca4d3b58 TRAP: 0300 Not tainted (5.6.0-rc1-s3k-dev-00824-g84195dc6c58a) MSR: 00001032 <ME,IR,DR,RI> CR: 2a4d3c52 XER: 00000000 DAR: 0000e268 DSISR: c0000000 GPR00: c000b09c ca4d3c10 c66d0620 00000000 ca4d3c60 00000000 00009032 00000000 GPR08: 00020000 00000000 c087de44 c000afe0 c66d0ad0 100d3dd6 fffffff3 00000000 GPR16: 00000000 00000041 00000000 ca4d3d70 00000000 00000000 0000416d 00000000 GPR24: 00000004 c53b6128 00000000 0000e268 00000000 c07c0000 c07bb6fc ca4d3c60 NIP [c000ec34] kprobe_handler+0x128/0x290 LR [c000ecd8] kprobe_handler+0x1cc/0x290 Call Trace: [ca4d3c30] [c000b09c] program_check_exception+0xbc/0x6fc [ca4d3c50] [c000e43c] ret_from_except_full+0x0/0x4 --- interrupt: 700 at 0xe268 Instruction dump: 913e0008 81220000 38600001 3929ffff 91220000 80010024 bb410008 7c0803a6 38210020 4e800020 38600000 4e800020 <813b0000> 6d2a7fe0 2f8a0008 419e0154 ---[ end trace 5b9152d4cdadd06d ]--- kprobe is not prepared to handle events in real mode and functions running in real mode should have been blacklisted, so kprobe_handler() can safely bail out telling 'this trap is not mine' for any trap that happened while in real-mode. If the trap happened with MSR_IR or MSR_DR cleared, return 0 immediately. Reported-by: Larry Finger <Larry.Finger@lwfinger.net> Fixes: 6cc89bad60a6 ("powerpc/kprobes: Invoke handlers directly") Cc: stable@vger.kernel.org # v4.10+ Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/424331e2006e7291a1bfe40e7f3fa58825f565e1.1582054578.git.christophe.leroy@c-s.fr
2020-03-25powerpc/eeh: Rework eeh_ops->probe()Oliver O'Halloran
With the EEH early probe now being pseries specific there's no need for eeh_ops->probe() to take a pci_dn. Instead, we can make it take a pci_dev and use the probe function to map a pci_dev to an eeh_dev. This allows the platform to implement it's own method for finding (or creating) an eeh_dev for a given pci_dev which also removes a use of pci_dn in generic EEH code. This patch also renames eeh_device_add_late() to eeh_device_probe(). This better reflects what it does does and removes the last vestiges of the early/late EEH probe split. Reviewed-by: Sam Bobroff <sbobroff@linux.ibm.com> Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200306073904.4737-6-oohall@gmail.com
2020-03-25powerpc/eeh: Make early EEH init pseries specificOliver O'Halloran
The eeh_ops->probe() function is called from two different contexts: 1. On pseries, where we set EEH_PROBE_MODE_DEVTREE, it's called in eeh_add_device_early() which is supposed to run before we create a pci_dev. 2. On PowerNV, where we set EEH_PROBE_MODE_DEV, it's called in eeh_device_add_late() which is supposed to run *after* the pci_dev is created. The "early" probe is required because PAPR requires that we perform an RTAS call to enable EEH support on a device before we start interacting with it via config space or MMIO. This requirement doesn't exist on PowerNV and shoehorning two completely separate initialisation paths into a common interface just results in a convoluted code everywhere. Additionally the early probe requires the probe function to take an pci_dn rather than a pci_dev argument. We'd like to make pci_dn a pseries specific data structure since there's no real requirement for them on PowerNV. To help both goals move the early probe into the pseries containment zone so the platform depedence is more explicit. Reviewed-by: Sam Bobroff <sbobroff@linux.ibm.com> Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200306073904.4737-5-oohall@gmail.com
2020-03-25powerpc/eeh: Remove PHB check in probeOliver O'Halloran
This check for a missing PHB has existing in various forms since the initial PPC64 port was upstreamed in 2002. The idea seems to be that we need to guard against creating pci-specific data structures for the non-pci children of a PCI device tree node (e.g. USB devices). However, we only create pci_dn structures for DT nodes that correspond to PCI devices so there's not much point in doing this check in the eeh_probe path. Reviewed-by: Sam Bobroff <sbobroff@linux.ibm.com> Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200306073904.4737-4-oohall@gmail.com
2020-03-25powerpc/eeh: Do early EEH init only when requiredOliver O'Halloran
The pci hotplug helper (pci_hp_add_devices()) calls eeh_add_device_tree_early() to scan the device-tree for new PCI devices and do the early EEH probe before the device is scanned. This early probe is a no-op in a lot of cases because: a) The early init is only required to satisfy a PAPR requirement that EEH be configured before we start doing config accesses. On PowerNV it is a no-op. b) It's a no-op for devices that have already had their eeh_dev initialised. There are four callers of pci_hp_add_devices(): 1. arch/powerpc/kernel/eeh_driver.c Here the hotplug helper is called when re-scanning pci_devs that were removed during an EEH recovery pass. The EEH stat for each removed device (the eeh_dev) is retained across a recovery pass so the early init is a no-op in this case. 2. drivers/pci/hotplug/pnv_php.c This is also a no-op since the PowerNV hotplug driver is, suprisingly, PowerNV specific. 3. drivers/pci/hotplug/rpaphp_core.c 4. drivers/pci/hotplug/rpaphp_pci.c In these two cases new devices have been hotplugged and FW has provided new DT nodes for each. These are the only two cases where the EEH we might have new PCI device nodes in the DT so these are the only two cases where the early EEH probe needs to be done. We can move the calls to eeh_add_device_tree_early() to the locations where it's needed and remove it from the generic path. This is preparation for making the early EEH probe pseries specific. Reviewed-by: Sam Bobroff <sbobroff@linux.ibm.com> Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200306073904.4737-3-oohall@gmail.com
2020-03-25powerpc/eeh: Remove eeh_add_device_tree_late()Oliver O'Halloran
On pseries and PowerNV pcibios_bus_add_device() calls eeh_add_device_late() so there's no need to do a separate tree traversal to bind the eeh_dev and pci_dev together setting up the PHB at boot. As a result we can remove eeh_add_device_tree_late(). Reviewed-by: Sam Bobroff <sbobroff@linux.ibm.com> Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200306073904.4737-2-oohall@gmail.com
2020-03-25powerpc/eeh: Add sysfs files in late probeOliver O'Halloran
Move creating the EEH specific sysfs files into eeh_add_device_late() rather than being open-coded all over the place. Calling the function is generally done immediately after calling eeh_add_device_late() anyway. This is also a correctness fix since currently the sysfs files will be added even if the EEH probe happens to fail. Similarly, on pseries we currently add the sysfs files before calling eeh_add_device_late(). This is flat-out broken since the sysfs files require the pci_dev->dev.archdata.edev pointer to be set, and that is done in eeh_add_device_late(). Reviewed-by: Sam Bobroff <sbobroff@linux.ibm.com> Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200306073904.4737-1-oohall@gmail.com
2020-03-25powerpc/64: Prevent stack protection in early bootMichael Ellerman
The previous commit reduced the amount of code that is run before we setup a paca. However there are still a few remaining functions that run with no paca, or worse, with an arbitrary value in r13 that will be used as a paca pointer. In particular the stack protector canary is stored in the paca, so if stack protector is activated for any of these functions we will read the stack canary from wherever r13 points. If r13 happens to point outside of memory we will get a machine check / checkstop. For example if we modify initialise_paca() to trigger stack protection, and then boot in the mambo simulator with r13 poisoned in skiboot before calling the kernel: DEBUG: 19952232: (19952232): INSTRUCTION: PC=0xC0000000191FC1E8: [0x3C4C006D]: addis r2,r12,0x6D [fetch] DEBUG: 19952236: (19952236): INSTRUCTION: PC=0xC00000001807EAD8: [0x7D8802A6]: mflr r12 [fetch] FATAL ERROR: 19952276: (19952276): Check Stop for 0:0: Machine Check with ME bit of MSR off DEBUG: 19952276: (19952276): INSTRUCTION: PC=0xC0000000191FCA7C: [0xE90D0CF8]: ld r8,0xCF8(r13) [Instruction Failed] INFO: 19952276: (19952277): ** Execution stopped: Mambo Error, Machine Check Stop, ** systemsim % bt pc: 0xC0000000191FCA7C initialise_paca+0x54 lr: 0xC0000000191FC22C early_setup+0x44 stack:0x00000000198CBED0 0x0 +0x0 stack:0x00000000198CBF00 0xC0000000191FC22C early_setup+0x44 stack:0x00000000198CBF90 0x1801C968 +0x1801C968 So annotate the relevant functions to ensure stack protection is never enabled for them. Fixes: 06ec27aea9fc ("powerpc/64: add stack protector support") Cc: stable@vger.kernel.org # v4.20+ Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200320032116.1024773-2-mpe@ellerman.id.au
2020-03-25powerpc/64: Setup a paca before parsing device tree etc.Daniel Axtens
Currently we set up the paca after parsing the device tree for CPU features. Prior to that, r13 contains random data, which means there is random data in r13 while we're running the generic dt parsing code. This random data varies depending on whether we boot through a vmlinux or a zImage: for the vmlinux case it's usually around zero, but for zImages we see random values like 912a72603d420015. This is poor practice, and can also lead to difficult-to-debug crashes. For example, when kcov is enabled, the kcov instrumentation attempts to read preempt_count out of the current task, which goes via the paca. This then crashes in the zImage case. Similarly stack protector can cause crashes if r13 is bogus, by reading from the stack canary in the paca. To resolve this: - move the paca setup to before the CPU feature parsing. - because we no longer have access to CPU feature flags in paca setup, change the HV feature test in the paca setup path to consider the actual value of the MSR rather than the CPU feature. Translations get switched on once we leave early_setup, so I think we'd already catch any other cases where the paca or task aren't set up. Boot tested on a P9 guest and host. Fixes: fb0b0a73b223 ("powerpc: Enable kcov") Fixes: 06ec27aea9fc ("powerpc/64: add stack protector support") Cc: stable@vger.kernel.org # v4.20+ Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com> Suggested-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Daniel Axtens <dja@axtens.net> [mpe: Reword comments & change log a bit to mention stack protector] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200320032116.1024773-1-mpe@ellerman.id.au
2020-03-25powerpc/32s: reorder Linux PTE bits to better match Hash PTE bits.Christophe Leroy
Reorder Linux PTE bits to (almost) match Hash PTE bits. RW Kernel : PP = 00 RO Kernel : PP = 00 RW User : PP = 01 RO User : PP = 11 So naturally, we should have _PAGE_USER = 0x001 _PAGE_RW = 0x002 Today 0x001 and 0x002 and _PAGE_PRESENT and _PAGE_HASHPTE which both are software only bits. Switch _PAGE_USER and _PAGE_PRESET Switch _PAGE_RW and _PAGE_HASHPTE This allows to remove a few insns. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/c4d6c18a7f8d9d3b899bc492f55fbc40ef38896a.1583861325.git.christophe.leroy@c-s.fr
2020-03-25powerpc/kprobes: Remove redundant codeChristophe Leroy
At the time being we have something like if (something) { p = get(); if (p) { if (something_wrong) goto out; ... return; } else if (a != b) { if (some_error) goto out; ... } goto out; } p = get(); if (!p) { if (a != b) { if (some_error) goto out; ... } goto out; } This is similar to p = get(); if (!p) { if (a != b) { if (some_error) goto out; ... } goto out; } if (something) { if (something_wrong) goto out; ... return; } Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> [mpe: Reflow the comment that was moved] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/07a17425743600460ce35fa9432d42487a825583.1582099499.git.christophe.leroy@c-s.fr
2020-03-25powerpc/64s: Fix section mismatch warnings from boot codeMichael Ellerman
We currently have two section mismatch warnings: The function __boot_from_prom() references the function __init prom_init(). The function start_here_common() references the function __init start_kernel(). The warnings are correct, we do have branches from non-init code into init code, which is freed after boot. But we don't expect to ever execute any of that early boot code after boot, if we did that would be a bug. In particular calling into OF after boot would be fatal because OF is no longer resident. So for now fix the warnings by marking the relevant functions as __REF, which puts them in the ".ref.text" section. This causes some reordering of the functions in the final link: @@ -217,10 +217,9 @@ c00000000000b088 t generic_secondary_common_init c00000000000b124 t __mmu_off c00000000000b14c t __start_initialization_multiplatform -c00000000000b1ac t __boot_from_prom -c00000000000b1ec t __after_prom_start -c00000000000b260 t p_end -c00000000000b27c T copy_and_flush +c00000000000b1ac t __after_prom_start +c00000000000b220 t p_end +c00000000000b23c T copy_and_flush c00000000000b300 T __secondary_start c00000000000b300 t copy_to_here c00000000000b344 t start_secondary_prolog @@ -228,8 +227,9 @@ c00000000000b36c t enable_64b_mode c00000000000b388 T relative_toc c00000000000b3a8 t p_toc -c00000000000b3b0 t start_here_common -c00000000000b3d0 t start_here_multiplatform +c00000000000b3b0 t __boot_from_prom +c00000000000b3f0 t start_here_multiplatform +c00000000000b480 t start_here_common c00000000000b880 T system_call_common c00000000000b974 t system_call c00000000000b9dc t system_call_exit In particular __boot_from_prom moves after copy_to_here, which means it's not copied to zero in the first stage of copy of the kernel to zero. But that's OK, because we only call __boot_from_prom before we do the copy, so it makes no difference when it's copied. The call sequence is: __start -> __start_initialization_multiplatform -> __boot_from_prom -> __start -> __start_initialization_multiplatform -> __after_prom_start -> copy_and_flush -> copy_and_flush (relocated to 0) -> start_here_multiplatform -> early_setup Reported-by: Mauricio Faria de Oliveira <mauricfo@linux.ibm.com> Reported-by: Roman Bolshakov <r.bolshakov@yadro.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225031328.14676-1-mpe@ellerman.id.au
2020-03-25powerpc/prom_init: Pass the "os-term" message to hypervisorAlexey Kardashevskiy
The "os-term" RTAS calls has one argument with a message address of OS termination cause. rtas_os_term() already passes it but the recently added prom_init's version of that missed it; it also does not fill args correctly. This passes the message address and initializes the number of arguments. Fixes: 6a9c930bd775 ("powerpc/prom_init: Add the ESM call to prom_init") Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200312074404.87293-1-aik@ozlabs.ru
2020-03-19bpf: Support llvm-objcopy for vmlinux BTFFangrui Song
Simplify gen_btf logic to make it work with llvm-objcopy. The existing 'file format' and 'architecture' parsing logic is brittle and does not work with llvm-objcopy/llvm-objdump. 'file format' output of llvm-objdump>=11 will match GNU objdump, but 'architecture' (bfdarch) may not. .BTF in .tmp_vmlinux.btf is non-SHF_ALLOC. Add the SHF_ALLOC flag because it is part of vmlinux image used for introspection. C code can reference the section via linker script defined __start_BTF and __stop_BTF. This fixes a small problem that previous .BTF had the SHF_WRITE flag (objcopy -I binary -O elf* synthesized .data). Additionally, `objcopy -I binary` synthesized symbols _binary__btf_vmlinux_bin_start and _binary__btf_vmlinux_bin_stop (not used elsewhere) are replaced with more commonplace __start_BTF and __stop_BTF. Add 2>/dev/null because GNU objcopy (but not llvm-objcopy) warns "empty loadable segment detected at vaddr=0xffffffff81000000, is this intentional?" We use a dd command to change the e_type field in the ELF header from ET_EXEC to ET_REL so that lld will accept .btf.vmlinux.bin.o. Accepting ET_EXEC as an input file is an extremely rare GNU ld feature that lld does not intend to support, because this is error-prone. The output section description .BTF in include/asm-generic/vmlinux.lds.h avoids potential subtle orphan section placement issues and suppresses --orphan-handling=warn warnings. Fixes: df786c9b9476 ("bpf: Force .BTF section start to zero when dumping from vmlinux") Fixes: cb0cc635c7a9 ("powerpc: Include .BTF section") Reported-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: Fangrui Song <maskray@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Tested-by: Stanislav Fomichev <sdf@google.com> Tested-by: Andrii Nakryiko <andriin@fb.com> Reviewed-by: Stanislav Fomichev <sdf@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Link: https://github.com/ClangBuiltLinux/linux/issues/871 Link: https://lore.kernel.org/bpf/20200318222746.173648-1-maskray@google.com
2020-03-13powerpc/vdso: remove deprecated VDS64_HAS_DESCRIPTORS referencesJoe Lawrence
The original 2005 patch that introduced the powerpc vdso, pre-git ("ppc64: Implement a vDSO and use it for signal trampoline") notes that: ... symbols exposed by the vDSO aren't "normal" function symbols, apps can't be expected to link against them directly, the vDSO's are both seen as if they were linked at 0 and the symbols just contain offsets to the various functions. This is done on purpose to avoid a relocation step (ppc64 functions normally have descriptors with abs addresses in them). When glibc uses those functions, it's expected to use it's own trampolines that know how to reach them. Despite that explanation, there remains dead #ifdef VDS64_HAS_DESCRIPTORS code-blocks that provide alternate function definitions that setup function descriptors. Since VDS64_HAS_DESCRIPTORS has been unused for all these years, we might as well finally remove it from the codebase. Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200224211848.26087-1-joe.lawrence@redhat.com
2020-03-10Merge branch 'fixes' into nextMichael Ellerman
Merge in our fixes branch. In particular we want to merge the TM and KUAP fixes, so we can add selftests for them in next.
2020-03-04powerpc/numa: Remove late request for home node associativitySrikar Dronamraju
With commit ("powerpc/numa: Early request for home node associativity"), commit 2ea626306810 ("powerpc/topology: Get topology for shared processors at boot") which was requesting home node associativity becomes redundant. Hence remove the late request for home node associativity. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Reported-by: Abdul Haleem <abdhalee@linux.vnet.ibm.com> Reviewed-by: Nathan Lynch <nathanl@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200129135301.24739-6-srikar@linux.vnet.ibm.com
2020-03-04powerpc/smp: Use nid as fallback for package_idSrikar Dronamraju
package_id is to match cores that are part of the same chip. On PowerNV machines, package_id defaults to chip_id. However ibm,chip_id property is not present in device-tree of PowerVM LPARs. Hence lscpu output shows one core per socket and multiple cores. To overcome this, use nid as the package_id on PowerVM LPARs. Before the patch: Architecture: ppc64le Byte Order: Little Endian CPU(s): 128 On-line CPU(s) list: 0-127 Thread(s) per core: 8 Core(s) per socket: 1 <---------------------- Socket(s): 16 <---------------------- NUMA node(s): 2 Model: 2.2 (pvr 004e 0202) Model name: POWER9 (architected), altivec supported Hypervisor vendor: pHyp Virtualization type: para L1d cache: 32K L1i cache: 32K L2 cache: 512K L3 cache: 10240K NUMA node0 CPU(s): 0-63 NUMA node1 CPU(s): 64-127 # # cat /sys/devices/system/cpu/cpu0/topology/physical_package_id -1 After the patch: Architecture: ppc64le Byte Order: Little Endian CPU(s): 128 On-line CPU(s) list: 0-127 Thread(s) per core: 8 <--------------------- Core(s) per socket: 8 <--------------------- Socket(s): 2 NUMA node(s): 2 Model: 2.2 (pvr 004e 0202) Model name: POWER9 (architected), altivec supported Hypervisor vendor: pHyp Virtualization type: para L1d cache: 32K L1i cache: 32K L2 cache: 512K L3 cache: 10240K NUMA node0 CPU(s): 0-63 NUMA node1 CPU(s): 64-127 # # cat /sys/devices/system/cpu/cpu0/topology/physical_package_id 0 Now lscpu output is more in line with the system configuration. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> [mpe: Use pkg_id instead of ppid, tweak change log and comment] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200129135121.24617-1-srikar@linux.vnet.ibm.com
2020-03-04powerpc/irq: Use current_stack_pointer in do_IRQ()Christophe Leroy
Until commit 7306e83ccf5c ("powerpc: Don't use CURRENT_THREAD_INFO to find the stack"), the current stack base address was obtained by calling current_thread_info(). That inline function was simply masking out the value of r1. In that commit, it was changed to using current_stack_pointer() (since renamed current_stack_frame()), which is a heavier function as it is an outline assembly function which cannot be inlined and which reads the content of the stack at 0(r1). Convert to using current_stack_pointer for geting r1 and masking out its value to obtain the base address of the stack pointer as before. Fixes: 7306e83ccf5c ("powerpc: Don't use CURRENT_THREAD_INFO to find the stack") Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200220115141.2707-5-mpe@ellerman.id.au
2020-03-04powerpc/irq: use IS_ENABLED() in check_stack_overflow()Christophe Leroy
Instead of #ifdef, use IS_ENABLED(CONFIG_DEBUG_STACKOVERFLOW). This enable GCC to check for code validity even when the option is not selected. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200220115141.2707-4-mpe@ellerman.id.au
2020-03-04powerpc/irq: Use current_stack_pointer in check_stack_overflow()Christophe Leroy
The purpose of check_stack_overflow() is to verify that the stack has not overflowed. To really know whether the stack pointer is still within boundaries, the check must be done directly on the value of r1. So use current_stack_pointer, which returns the current value of r1, rather than current_stack_frame() which causes a frame to be created and then returns that value. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200220115141.2707-3-mpe@ellerman.id.au
2020-03-04powerpc: Rename current_stack_pointer() to current_stack_frame()Michael Ellerman
current_stack_pointer(), which was called __get_SP(), used to just return the value in r1. But that caused problems in some cases, so it was turned into a function in commit bfe9a2cfe91a ("powerpc: Reimplement __get_SP() as a function not a define"). Because it's a function in a separate compilation unit to all its callers, it has the effect of causing a stack frame to be created, and then returns the address of that frame. This is good in some cases like those described in the above commit, but in other cases it's overkill, we just need to know what stack page we're on. On some other arches current_stack_pointer is just a register global giving the stack pointer, and we'd like to do that too. So rename our current_stack_pointer() to current_stack_frame() to make that possible. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr> Link: https://lore.kernel.org/r/20200220115141.2707-1-mpe@ellerman.id.au
2020-03-04powerpc/kernel/sysfs: Add new config option PMU_SYSFS to enable PMU SPRs ↵Kajol Jain
sysfs file creation Many of the performance monitoring unit (PMU) SPRs are exposed in the sysfs. This may not be a desirable since "perf" API is the primary interface to program PMU and collect counter data in the system. But that said, we cant remove these sysfs files since we dont whether anyone/anything is using them. So the patch adds a new CONFIG option 'CONFIG_PMU_SYSFS' (user selectable) to be used in sysfs file creation for PMU SPRs. New option by default is disabled, but can be enabled if user needs it. Tested this patch behaviour in powernv and pseries machines. Patch is also tested for pmac32_defconfig. Signed-off-by: Kajol Jain <kjain@linux.ibm.com> Tested-by: Nageswara R Sastry <nasastry@in.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200214080606.26872-2-kjain@linux.ibm.com
2020-03-04powerpc/kernel/sysfs: Refactor current sysfs.cMadhavan Srinivasan
An attempt to refactor the current sysfs.c file. To start with a big chuck of macro #defines and dscr functions are moved to start of the file. Secondly, HAS_ #define macros are cleanup based on CONFIG_ options Finally new HAS_ macro added: 1. HAS_PPC_PA6T (for PA6T) to separate out non-PMU SPRs. 2. HAS_PPC_PMC56 to separate out PMC SPR's from HAS_PPC_PMC_CLASSIC which come under CONFIG_PPC64. Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200214080606.26872-1-kjain@linux.ibm.com
2020-03-04powerpc/kernel: no need to check return value of debugfs_create functionsGreg Kroah-Hartman
When calling debugfs functions, there is no need to ever check the return value. The function can work or not, but the code logic should never do something different based on this. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200209105901.1620958-1-gregkh@linuxfoundation.org
2020-02-28powerpc: fix hardware PMU exception bug on PowerVM compatibility mode systemsDesnes A. Nunes do Rosario
PowerVM systems running compatibility mode on a few Power8 revisions are still vulnerable to the hardware defect that loses PMU exceptions arriving prior to a context switch. The software fix for this issue is enabled through the CPU_FTR_PMAO_BUG cpu_feature bit, nevertheless this bit also needs to be set for PowerVM compatibility mode systems. Fixes: 68f2f0d431d9ea4 ("powerpc: Add a cpu feature CPU_FTR_PMAO_BUG") Signed-off-by: Desnes A. Nunes do Rosario <desnesn@linux.ibm.com> Reviewed-by: Leonardo Bras <leonardo@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200227134715.9715-1-desnesn@linux.ibm.com
2020-02-26powerpc/32: don't restore r0, r6-r8 on exception entry path after ↵Christophe Leroy
trace_hardirqs_off() Since commit b86fb88855ea ("powerpc/32: implement fast entry for syscalls on non BOOKE") and commit 1a4b739bbb4f ("powerpc/32: implement fast entry for syscalls on BOOKE"), syscalls don't use the exception entry path anymore. It is therefore pointless to restore r0 and r6-r8 after calling trace_hardirqs_off(). In the meantime, drop the '2:' label which is unused and misleading. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/d2c6dc65d27e83964eb05f16a126161ab6455eea.1578388585.git.christophe.leroy@c-s.fr
2020-02-24powerpc: Include .BTF sectionNaveen N. Rao
Selecting CONFIG_DEBUG_INFO_BTF results in the below warning from ld: ld: warning: orphan section `.BTF' from `.btf.vmlinux.bin.o' being placed in section `.BTF' Include .BTF section in vmlinux explicitly to fix the same. Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200220113132.857132-1-naveen.n.rao@linux.vnet.ibm.com
2020-02-24powerpc/watchpoint: Don't call dar_within_range() for Book3SRavi Bangoria
DAR is set to the first byte of overlap between actual access and watched range at DSI on Book3S processor. But actual access range might or might not be within user asked range. So for Book3S, it must not call dar_within_range(). This revert portion of commit 39413ae00967 ("powerpc/hw_breakpoints: Rewrite 8xx breakpoints to allow any address range size."). Before patch: # ./tools/testing/selftests/powerpc/ptrace/perf-hwbreak ... TESTED: No overlap FAILED: Partial overlap: 0 != 2 TESTED: Partial overlap TESTED: No overlap FAILED: Full overlap: 0 != 2 failure: perf_hwbreak After patch: TESTED: No overlap TESTED: Partial overlap TESTED: Partial overlap TESTED: No overlap TESTED: Full overlap success: perf_hwbreak Fixes: 39413ae00967 ("powerpc/hw_breakpoints: Rewrite 8xx breakpoints to allow any address range size.") Reported-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200222082049.330435-1-ravi.bangoria@linux.ibm.com
2020-02-19powerpc: Don't use thread struct for saving SRR0/1 on syscall.Christophe Leroy
CR0 can be saved later, and CTR can also be used for saving. Keep SRR1 in r9 and stash SRR0 in CTR, this avoids using thread_struct in memory for that. Saves 3 cycles (ie 1%) in null_syscall selftest on 8xx. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/b94c3bc03bac9431fec2dadb686384c481889422.1580470483.git.christophe.leroy@c-s.fr
2020-02-19powerpc/32: Warn and return ENOSYS on syscalls from kernelChristophe Leroy
Since commit b86fb88855ea ("powerpc/32: implement fast entry for syscalls on non BOOKE") and commit 1a4b739bbb4f ("powerpc/32: implement fast entry for syscalls on BOOKE"), syscalls from kernel are unexpected and can have catastrophic consequences as it will destroy the kernel stack. Test MSR_PR on syscall entry. In case syscall is from kernel, emit a warning and return ENOSYS error. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/8ee3bdbbdfdfc64ca7001e90c43b2aee6f333578.1580470482.git.christophe.leroy@c-s.fr
2020-02-19powerpc/fadump: sysfs for fadump memory reservationSourabh Jain
Add a sys interface to allow querying the memory reserved by FADump for saving the crash dump. Also added Documentation/ABI for the new sysfs file. Signed-off-by: Sourabh Jain <sourabhjain@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20191211160910.21656-7-sourabhjain@linux.ibm.com
2020-02-19powerpc/fadump: Reorganize /sys/kernel/fadump_* sysfs filesSourabh Jain
As the number of FADump sysfs files increases it is hard to manage all of them inside /sys/kernel directory. It's better to have all the FADump related sysfs files in a dedicated directory /sys/kernel/fadump. But in order to maintain backward compatibility a symlink has been added for every sysfs that has moved to new location. As the FADump sysfs files are now part of a dedicated directory there is no need to prefix their name with fadump_, hence sysfs file names are also updated. For example fadump_enabled sysfs file is now referred as enabled. Also consolidate ABI documentation for all the FADump sysfs files in a single file Documentation/ABI/testing/sysfs-kernel-fadump. Signed-off-by: Sourabh Jain <sourabhjain@linux.ibm.com> Tested-by: Michal Suchanek <msuchanek@suse.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20191211160910.21656-4-sourabhjain@linux.ibm.com
2020-02-19powerpc/process: Remove unneccessary #ifdef CONFIG_PPC64 in copy_thread_tls()Christophe Leroy
is_32bit_task() exists on both PPC64 and PPC32, no need of an ifdefery. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Michal Suchanek <msuchanek@suse.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/6ecbda05b4119c40222dc8ec284604e1597c9bff.1580327381.git.christophe.leroy@c-s.fr
2020-02-19powerpc/entry: Fix an #if which should be an #ifdef in entry_32.SChristophe Leroy
Fixes: 12c3f1fd87bf ("powerpc/32s: get rid of CPU_FTR_601 feature") Cc: stable@vger.kernel.org # v5.4+ Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/a99fc0ad65b87a1ba51cfa3e0e9034ee294c3e07.1582034961.git.christophe.leroy@c-s.fr
2020-02-18powerpc/6xx: Fix power_save_ppc32_restore() with CONFIG_VMAP_STACKChristophe Leroy
power_save_ppc32_restore() is called during exception entry, before re-enabling the MMU. It substracts KERNELBASE from the address of nap_save_msscr0 to access it. With CONFIG_VMAP_STACK enabled, data MMU translation has already been re-enabled, so power_save_ppc32_restore() has to access nap_save_msscr0 by its virtual address. Reported-by: Larry Finger <Larry.Finger@lwfinger.net> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Fixes: cd08f109e262 ("powerpc/32s: Enable CONFIG_VMAP_STACK") Tested-by: Larry Finger <Larry.Finger@lwfinger.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/7bce32ccbab3ba3e3e0f27da6961bf6313df97ed.1581663140.git.christophe.leroy@c-s.fr