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2020-10-13Merge tag 'perf-kprobes-2020-10-12' of ↵Linus Torvalds1-50/+3
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf/kprobes updates from Ingo Molnar: "This prepares to unify the kretprobe trampoline handler and make kretprobe lockless (those patches are still work in progress)" * tag 'perf-kprobes-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: kprobes: Fix to check probe enabled before disarm_kprobe_ftrace() kprobes: Make local functions static kprobes: Free kretprobe_instance with RCU callback kprobes: Remove NMI context check sparc: kprobes: Use generic kretprobe trampoline handler sh: kprobes: Use generic kretprobe trampoline handler s390: kprobes: Use generic kretprobe trampoline handler powerpc: kprobes: Use generic kretprobe trampoline handler parisc: kprobes: Use generic kretprobe trampoline handler mips: kprobes: Use generic kretprobe trampoline handler ia64: kprobes: Use generic kretprobe trampoline handler csky: kprobes: Use generic kretprobe trampoline handler arc: kprobes: Use generic kretprobe trampoline handler arm64: kprobes: Use generic kretprobe trampoline handler arm: kprobes: Use generic kretprobe trampoline handler x86/kprobes: Use generic kretprobe trampoline handler kprobes: Add generic kretprobe trampoline handler
2020-10-12Merge tag 'core-build-2020-10-12' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull orphan section checking from Ingo Molnar: "Orphan link sections were a long-standing source of obscure bugs, because the heuristics that various linkers & compilers use to handle them (include these bits into the output image vs discarding them silently) are both highly idiosyncratic and also version dependent. Instead of this historically problematic mess, this tree by Kees Cook (et al) adds build time asserts and build time warnings if there's any orphan section in the kernel or if a section is not sized as expected. And because we relied on so many silent assumptions in this area, fix a metric ton of dependencies and some outright bugs related to this, before we can finally enable the checks on the x86, ARM and ARM64 platforms" * tag 'core-build-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits) x86/boot/compressed: Warn on orphan section placement x86/build: Warn on orphan section placement arm/boot: Warn on orphan section placement arm/build: Warn on orphan section placement arm64/build: Warn on orphan section placement x86/boot/compressed: Add missing debugging sections to output x86/boot/compressed: Remove, discard, or assert for unwanted sections x86/boot/compressed: Reorganize zero-size section asserts x86/build: Add asserts for unwanted sections x86/build: Enforce an empty .got.plt section x86/asm: Avoid generating unused kprobe sections arm/boot: Handle all sections explicitly arm/build: Assert for unwanted sections arm/build: Add missing sections arm/build: Explicitly keep .ARM.attributes sections arm/build: Refactor linker script headers arm64/build: Assert for unwanted sections arm64/build: Add missing DWARF sections arm64/build: Use common DISCARDS in linker script arm64/build: Remove .eh_frame* sections due to unwind tables ...
2020-10-12Merge tag 'x86-irq-2020-10-12' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 irq updates from Thomas Gleixner: "Surgery of the MSI interrupt handling to prepare the support of upcoming devices which require non-PCI based MSI handling: - Cleanup historical leftovers all over the place - Rework the code to utilize more core functionality - Wrap XEN PCI/MSI interrupts into an irqdomain to make irqdomain assignment to PCI devices possible. - Assign irqdomains to PCI devices at initialization time which allows to utilize the full functionality of hierarchical irqdomains. - Remove arch_.*_msi_irq() functions from X86 and utilize the irqdomain which is assigned to the device for interrupt management. - Make the arch_.*_msi_irq() support conditional on a config switch and let the last few users select it" * tag 'x86-irq-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits) PCI: MSI: Fix Kconfig dependencies for PCI_MSI_ARCH_FALLBACKS x86/apic/msi: Unbreak DMAR and HPET MSI iommu/amd: Remove domain search for PCI/MSI iommu/vt-d: Remove domain search for PCI/MSI[X] x86/irq: Make most MSI ops XEN private x86/irq: Cleanup the arch_*_msi_irqs() leftovers PCI/MSI: Make arch_.*_msi_irq[s] fallbacks selectable x86/pci: Set default irq domain in pcibios_add_device() iommm/amd: Store irq domain in struct device iommm/vt-d: Store irq domain in struct device x86/xen: Wrap XEN MSI management into irqdomain irqdomain/msi: Allow to override msi_domain_alloc/free_irqs() x86/xen: Consolidate XEN-MSI init x86/xen: Rework MSI teardown x86/xen: Make xen_msi_init() static and rename it to xen_hvm_msi_init() PCI/MSI: Provide pci_dev_has_special_msi_domain() helper PCI_vmd_Mark_VMD_irqdomain_with_DOMAIN_BUS_VMD_MSI irqdomain/msi: Provide DOMAIN_BUS_VMD_MSI x86/irq: Initialize PCI/MSI domain at PCI init time x86/pci: Reducde #ifdeffery in PCI init code ...
2020-10-12Merge tag 'ras_updates_for_v5.10' of ↵Linus Torvalds5-20/+30
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RAS updates from Borislav Petkov: - Extend the recovery from MCE in kernel space also to processes which encounter an MCE in kernel space but while copying from user memory by sending them a SIGBUS on return to user space and umapping the faulty memory, by Tony Luck and Youquan Song. - memcpy_mcsafe() rework by splitting the functionality into copy_mc_to_user() and copy_mc_to_kernel(). This, as a result, enables support for new hardware which can recover from a machine check encountered during a fast string copy and makes that the default and lets the older hardware which does not support that advance recovery, opt in to use the old, fragile, slow variant, by Dan Williams. - New AMD hw enablement, by Yazen Ghannam and Akshay Gupta. - Do not use MSR-tracing accessors in #MC context and flag any fault while accessing MCA architectural MSRs as an architectural violation with the hope that such hw/fw misdesigns are caught early during the hw eval phase and they don't make it into production. - Misc fixes, improvements and cleanups, as always. * tag 'ras_updates_for_v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mce: Allow for copy_mc_fragile symbol checksum to be generated x86/mce: Decode a kernel instruction to determine if it is copying from user x86/mce: Recover from poison found while copying from user space x86/mce: Avoid tail copy when machine check terminated a copy from user x86/mce: Add _ASM_EXTABLE_CPY for copy user access x86/mce: Provide method to find out the type of an exception handler x86/mce: Pass pointer to saved pt_regs to severity calculation routines x86/copy_mc: Introduce copy_mc_enhanced_fast_string() x86, powerpc: Rename memcpy_mcsafe() to copy_mc_to_{user, kernel}() x86/mce: Drop AMD-specific "DEFERRED" case from Intel severity rule list x86/mce: Add Skylake quirk for patrol scrub reported errors RAS/CEC: Convert to DEFINE_SHOW_ATTRIBUTE() x86/mce: Annotate mce_rd/wrmsrl() with noinstr x86/mce/dev-mcelog: Do not update kflags on AMD systems x86/mce: Stop mce_reign() from re-computing severity for every CPU x86/mce: Make mce_rdmsrl() panic on an inaccessible MSR x86/mce: Increase maximum number of banks to 64 x86/mce: Delay clearing IA32_MCG_STATUS to the end of do_machine_check() x86/MCE/AMD, EDAC/mce_amd: Remove struct smca_hwid.xec_bitmap RAS/CEC: Fix cec_init() prototype
2020-10-08seccomp: Move config option SECCOMP to arch/KconfigYiFei Zhu1-17/+0
In order to make adding configurable features into seccomp easier, it's better to have the options at one single location, considering especially that the bulk of seccomp code is arch-independent. An quick look also show that many SECCOMP descriptions are outdated; they talk about /proc rather than prctl. As a result of moving the config option and keeping it default on, architectures arm, arm64, csky, riscv, sh, and xtensa did not have SECCOMP on by default prior to this and SECCOMP will be default in this change. Architectures microblaze, mips, powerpc, s390, sh, and sparc have an outdated depend on PROC_FS and this dependency is removed in this change. Suggested-by: Jann Horn <jannh@google.com> Link: https://lore.kernel.org/lkml/CAG48ez1YWz9cnp08UZgeieYRhHdqh-ch7aNwc4JRBnGyrmgfMg@mail.gmail.com/ Signed-off-by: YiFei Zhu <yifeifz2@illinois.edu> [kees: added HAVE_ARCH_SECCOMP help text, tweaked wording] Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/9ede6ef35c847e58d61e476c6a39540520066613.1600951211.git.yifeifz2@illinois.edu
2020-10-08powerpc/time: Make get_tb() common to PPC32 and PPC64Christophe Leroy1-7/+3
mftbu() is always defined now, so the #ifdef can be removed and replaced by an IS_ENABLED(CONFIG_PPC64) inside the PPC32 version of get_tb(). Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/47e49717d2643169ffcbe5d507f184cf49f0fe95.1601556145.git.christophe.leroy@csgroup.eu
2020-10-08powerpc/time: Make get_tbl() common to PPC32 and PPC64Christophe Leroy1-7/+0
On PPC64, get_tbl() is defined as an alias of get_tb() which return the result of mftb(). That exactly the same as what the PPC32 version does. We don't need two versions. Remove the PPC64 definition of get_tbl() and use the PPC32 version for both. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/a8eaabb87d69534e533ebac805163e08146e05bd.1601556145.git.christophe.leroy@csgroup.eu
2020-10-08powerpc/time: Remove get_tbu()Christophe Leroy1-5/+0
get_tbu() is redundant with mftbu() and is not used anymore. Remove it. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/1746e2d11ea90c3f45877e1fcc6c79ce96cf6b98.1601556145.git.christophe.leroy@csgroup.eu
2020-10-08powerpc/time: Avoid using get_tbl() and get_tbu() internallyChristophe Leroy3-7/+7
get_tbl() is confusing as it returns the content of TBL register on PPC32 but the concatenation of TBL and TBU on PPC64. Use mftb() instead. Do the same with get_tbu() for consistency allthough it's name is less confusing. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/41573406a4eab98838decaa91649086fef1e6119.1601556145.git.christophe.leroy@csgroup.eu
2020-10-08powerpc/time: Make mftb() common to PPC32 and PPC64Christophe Leroy1-10/+4
No need to have two versions that are identical. CONFIG_PPC_CELL is only selected by PPC64 targets. CONFIG_E500 is the only PPC64 target selecting CONFIG_FSL_BOOK3E. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/6bf23ec744aab4ba63506a011f6a145ea35d620d.1601556145.git.christophe.leroy@csgroup.eu
2020-10-08powerpc/time: Rename mftbl() to mftb()Christophe Leroy2-4/+3
On PPC64, we have mftb(). On PPC32, we have mftbl() and an #define mftb() mftbl(). mftb() and mftbl() are equivalent, their purpose is to read the content of SPRN_TRBL, as returned by 'mftb' simplified instruction. binutils seems to define 'mftbl' instruction as an equivalent of 'mftb'. However in both 32 bits and 64 bits documentation, only 'mftb' is defined, and when performing a disassembly with objdump, the displayed instruction is 'mftb' No need to have two ways to do the same thing with different names, rename mftbl() to have only mftb(). Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/94dc68d3d9ef9eb549796d4b938b6ba0305a049b.1601556145.git.christophe.leroy@csgroup.eu
2020-10-08powerpc/32s: Remove #ifdef CONFIG_PPC_BOOK3S_32 in head_book3s_32.SChristophe Leroy1-15/+0
head_book3s_32.S is only built when CONFIG_PPC_BOOK3S_32 is selected. Remove all conditions based on CONFIG_PPC_BOOK3S_32 in the file. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/1b68632425d8866d147aea9005004e4594672211.1601975100.git.christophe.leroy@csgroup.eu
2020-10-08powerpc/32s: Rename head_32.S to head_book3s_32.SChristophe Leroy3-3/+5
Unlike PPC64 which had a single head_64.S, PPC32 are multiple ones. There is the head_32.S, selected by default based on the value of BITS and overridden based on some CONFIG_ values. This leads to thinking that it may be selected by different types of PPC32 platform but indeed it ends up being selected by book3s/32 only. Make that explicit by: - Not doing any default selection based on BITS. - Renaming head_32.S to head_book3s_32.S. - Get head_book3s_32.S selected only by CONFIG_PPC_BOOK3S_32. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> [mpe: Fix head_$(BITS).o reference in arch/powerpc/Makefile] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/319d379f696412681c66a987cc75e6abf8f958d2.1601975100.git.christophe.leroy@csgroup.eu
2020-10-08powerpc/32s: Setup the early hash table at all time.Christophe Leroy4-38/+17
At the time being, an early hash table is set up when CONFIG_KASAN is selected. There is nothing wrong with setting such an early hash table all the time, even if it is not used. This is a statically allocated 256 kB table which lies in the init data section. This makes the code simpler and may in the future allow to setup early IO mappings with fixmap instead of hard coding BATs. Put create_hpte() and flush_hash_pages() in the .ref.text section in order to avoid warning for the reference to early_hash[]. This reference is removed by MMU_init_hw_patch() before init memory is freed. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/b8f8101c368b8a6451844a58d7bd7d83c14cf2aa.1601566529.git.christophe.leroy@csgroup.eu
2020-10-08powerpc/time: Remove ifdef in get_dec() and set_dec()Christophe Leroy3-14/+12
Move SPRN_PIT definition in reg.h. This allows to remove ifdef in get_dec() and set_dec() and makes them more readable. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/3c9a6eb0fc040868ac59be66f338d08fd017668d.1601549945.git.christophe.leroy@csgroup.eu
2020-10-08powerpc: Remove get_tb_or_rtc()Christophe Leroy3-9/+4
601 is gone, get_tb_or_rtc() is equivalent to get_tb(). Replace the former by the later. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/3e8a13ee83418630c753c30cb722ae682d5b2d39.1601362098.git.christophe.leroy@csgroup.eu
2020-10-08powerpc: Remove __USE_RTC()Christophe Leroy2-71/+9
Now that PowerPC 601 is gone, __USE_RTC() is never true. Remove it. That also leads to removing get_rtc() and get_rtcl() Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/4757e1ed21fe1968c761ae081d1f3d790a9673f8.1601362098.git.christophe.leroy@csgroup.eu
2020-10-08powerpc: Tidy up a bit after removal of PowerPC 601.Christophe Leroy2-32/+24
The removal of the 601 left some standalone blocks from former if/else. Drop the { } and re-indent. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/31c4cd093963f22831bf388449056ee045533d3b.1601362098.git.christophe.leroy@csgroup.eu
2020-10-08powerpc: Remove support for PowerPC 601Christophe Leroy17-206/+17
PowerPC 601 has been retired. Remove all associated specific code. CPU_FTRS_PPC601 has CPU_FTR_COHERENT_ICACHE and CPU_FTR_COMMON. CPU_FTR_COMMON is already present via other CPU_FTRS. None of the remaining CPU selects CPU_FTR_COHERENT_ICACHE. So CPU_FTRS_PPC601 can be removed from the possible features, hence can be removed completely. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/60b725d55e21beec3335175c20b77903ff98284f.1601362098.git.christophe.leroy@csgroup.eu
2020-10-08powerpc: Remove PowerPC 601Christophe Leroy2-24/+2
Powerpc 601 is 25 years old. It is not selected by any defconfig. It requires a lot of special handling as it deviates from the standard 6xx. Retire it. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/00a6948d659e017f8ca63437d1384222c3aede57.1601362098.git.christophe.leroy@csgroup.eu
2020-10-08powerpc: Drop SYNC_601() ISYNC_601() and SYNC()Christophe Leroy7-45/+2
Those macros are now empty at all time. Drop them. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/7990bb63fc53e460bfa94f8040184881d9e6fbc3.1601362098.git.christophe.leroy@csgroup.eu
2020-10-08powerpc: Remove CONFIG_PPC601_SYNC_FIXChristophe Leroy2-21/+0
This config option isn't in any defconfig. The very first versions of Powerpc 601 have a bug which requires additional sync before and/or after some instructions. This was more than 25 years ago and time has come to retire those buggy versions of the 601 from the kernel. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/55b46bff16705b1ae7bf0a60ccd522b1010ebf75.1601362098.git.christophe.leroy@csgroup.eu
2020-10-08powerpc: Remove SYNC on non 6xxChristophe Leroy3-3/+0
SYNC is usefull for Powerpc 601 only. On everything else, SYNC is empty. Remove it from code that is not made to run on 6xx. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/27951fa6c9a8f80724d1bc81a6117ac32343a55d.1601362098.git.christophe.leroy@csgroup.eu
2020-10-08powerpc/papr_scm: Add PAPR command family to pass-through command-setVaibhav Jain1-0/+3
Add NVDIMM_FAMILY_PAPR to the list of valid 'dimm_family_mask' acceptable by papr_scm. This is needed as since commit 92fe2aa859f5 ("libnvdimm: Validate command family indices") libnvdimm performs a validation of 'nd_cmd_pkg.nd_family' received as part of ND_CMD_CALL processing to ensure only known command families can use the general ND_CMD_CALL pass-through functionality. Without this change the ND_CMD_CALL pass-through targeting NVDIMM_FAMILY_PAPR error out with -EINVAL. Fixes: 92fe2aa859f5 ("libnvdimm: Validate command family indices") Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200913211904.24472-1-vaibhav@linux.ibm.com
2020-10-08powerpc/lmb-size: Use addr #size-cells value when fetching lmb-sizeAneesh Kumar K.V2-7/+13
Make it consistent with other usages. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201007114836.282468-5-aneesh.kumar@linux.ibm.com
2020-10-08powerpc/book3s64/radix: Make radix_mem_block_size 64bitAneesh Kumar K.V2-2/+2
Similar to commit 89c140bbaeee ("pseries: Fix 64 bit logical memory block panic") make sure different variables tracking lmb_size are updated to be 64 bit. Fixes: af9d00e93a4f ("powerpc/mm/radix: Create separate mappings for hot-plugged memory") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201007114836.282468-4-aneesh.kumar@linux.ibm.com
2020-10-08powerpc/memhotplug: Make lmb size 64bitAneesh Kumar K.V1-14/+29
Similar to commit 89c140bbaeee ("pseries: Fix 64 bit logical memory block panic") make sure different variables tracking lmb_size are updated to be 64 bit. This was found by code audit. Cc: stable@vger.kernel.org Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201007114836.282468-3-aneesh.kumar@linux.ibm.com
2020-10-08powerpc/drmem: Make lmb_size 64 bitAneesh Kumar K.V1-2/+2
Similar to commit 89c140bbaeee ("pseries: Fix 64 bit logical memory block panic") make sure different variables tracking lmb_size are updated to be 64 bit. This was found by code audit. Cc: stable@vger.kernel.org Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Acked-by: Nathan Lynch <nathanl@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201007114836.282468-2-aneesh.kumar@linux.ibm.com
2020-10-08powerpc/security: Fix link stack flush instructionNicholas Piggin3-13/+33
The inline execution path for the hardware assisted branch flush instruction failed to set CTR to the correct value before bcctr, causing a crash when the feature is enabled. Fixes: 4d24e21cc694 ("powerpc/security: Allow for processors that flush the link stack using the special bcctr") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201007080605.64423-1-npiggin@gmail.com
2020-10-07powerpc/hv-gpci: Add sysfs files inside hv-gpci device to show cpumaskKajol Jain1-0/+18
Patch here adds a cpumask attr to hv_gpci pmu along with ABI documentation. Primary use to expose the cpumask is for the perf tool which has the capability to parse the driver sysfs folder and understand the cpumask file. Having cpumask file will reduce the number of perf command line parameters (will avoid "-C" option in the perf tool command line). It can also notify the user which is the current cpu used to retrieve the counter data. command:# cat /sys/devices/hv_gpci/cpumask 0 Signed-off-by: Kajol Jain <kjain@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201003074943.338618-5-kjain@linux.ibm.com
2020-10-07powerpc/perf/hv-gpci: Add cpu hotplug supportKajol Jain1-0/+46
Patch here adds cpu hotplug functions to hv_gpci pmu. A new cpuhp_state "CPUHP_AP_PERF_POWERPC_HV_GPCI_ONLINE" enum is added. The online callback function updates the cpumask only if its empty. As the primary intention of adding hotplug support is to designate a CPU to make HCALL to collect the counter data. The offline function test and clear corresponding cpu in a cpumask and update cpumask to any other active cpu. Signed-off-by: Kajol Jain <kjain@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201003074943.338618-4-kjain@linux.ibm.com
2020-10-07powerpc/perf/hv-gpci: Fix starting index valueKajol Jain1-3/+3
Commit 9e9f60108423f ("powerpc/perf/{hv-gpci, hv-common}: generate requests with counters annotated") adds a framework for defining gpci counters. In this patch, they adds starting_index value as '0xffffffffffffffff'. which is wrong as starting_index is of size 32 bits. Because of this, incase we try to run hv-gpci event we get error. In power9 machine: command#: perf stat -e hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/ -C 0 -I 1000 event syntax error: '..bie_count_and_time_tlbie_instructions_issued/' \___ value too big for format, maximum is 4294967295 This patch fix this issue and changes starting_index value to '0xffffffff' After this patch: command#: perf stat -e hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/ -C 0 -I 1000 1.000085786 1,024 hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/ 2.000287818 1,024 hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/ 2.439113909 17,408 hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/ Fixes: 9e9f60108423 ("powerpc/perf/{hv-gpci, hv-common}: generate requests with counters annotated") Signed-off-by: Kajol Jain <kjain@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201003074943.338618-1-kjain@linux.ibm.com
2020-10-07powerpc/pseries/eeh: Fix use of uninitialised variableOliver O'Halloran1-5/+4
If the RTAS call to query the PE address for a device fails we jump the err: label where an error message is printed along with the return code. However, the printed return code is from the "ret" variable which isn't set at that point since we assigned the result to "addr" instead. Fix this by consistently using the "ret" variable for the result of the RTAS call helpers an dropping the "addr" local variable" Fixes: 98ba956f6a38 ("powerpc/pseries/eeh: Rework device EEH PE determination") Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201007040903.819081-2-oohall@gmail.com
2020-10-07powerpc/eeh: Delete eeh_pe->config_addrOliver O'Halloran3-4/+3
The eeh_pe->config_addr field was supposed to be removed in commit 35d64734b643 ("powerpc/eeh: Clean up PE addressing") which made it largely unused. Finish the job. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201007040903.819081-1-oohall@gmail.com
2020-10-06pseries/hotplug-memory: hot-add: skip redundant LMB lookupScott Cheloha3-3/+8
During memory hot-add, dlpar_add_lmb() calls memory_add_physaddr_to_nid() to determine which node id (nid) to use when later calling __add_memory(). This is wasteful. On pseries, memory_add_physaddr_to_nid() finds an appropriate nid for a given address by looking up the LMB containing the address and then passing that LMB to of_drconf_to_nid_single() to get the nid. In dlpar_add_lmb() we get this address from the LMB itself. In short, we have a pointer to an LMB and then we are searching for that LMB *again* in order to find its nid. If we call of_drconf_to_nid_single() directly from dlpar_add_lmb() we can skip the redundant lookup. The only error handling we need to duplicate from memory_add_physaddr_to_nid() is the fallback to the default nid when drconf_to_nid_single() returns -1 (NUMA_NO_NODE) or an invalid nid. Skipping the extra lookup makes hot-add operations faster, especially on machines with many LMBs. Consider an LPAR with 126976 LMBs. In one test, hot-adding 126000 LMBs on an upatched kernel took ~3.5 hours while a patched kernel completed the same operation in ~2 hours: Unpatched (12450 seconds): Sep 9 04:06:31 ltc-brazos1 drmgr[810169]: drmgr: -c mem -a -q 126000 Sep 9 04:06:31 ltc-brazos1 kernel: pseries-hotplug-mem: Attempting to hot-add 126000 LMB(s) [...] Sep 9 07:34:01 ltc-brazos1 kernel: pseries-hotplug-mem: Memory at 20000000 (drc index 80000002) was hot-added Patched (7065 seconds): Sep 8 21:49:57 ltc-brazos1 drmgr[877703]: drmgr: -c mem -a -q 126000 Sep 8 21:49:57 ltc-brazos1 kernel: pseries-hotplug-mem: Attempting to hot-add 126000 LMB(s) [...] Sep 8 23:27:42 ltc-brazos1 kernel: pseries-hotplug-mem: Memory at 20000000 (drc index 80000002) was hot-added It should be noted that the speedup grows more substantial when hot-adding LMBs at the end of the drconf range. This is because we are skipping a linear LMB search. To see the distinction, consider smaller hot-add test on the same LPAR. A perf-stat run with 10 iterations showed that hot-adding 4096 LMBs completed less than 1 second faster on a patched kernel: Unpatched: Performance counter stats for 'drmgr -c mem -a -q 4096' (10 runs): 104,753.42 msec task-clock # 0.992 CPUs utilized ( +- 0.55% ) 4,708 context-switches # 0.045 K/sec ( +- 0.69% ) 2,444 cpu-migrations # 0.023 K/sec ( +- 1.25% ) 394 page-faults # 0.004 K/sec ( +- 0.22% ) 445,902,503,057 cycles # 4.257 GHz ( +- 0.55% ) (66.67%) 8,558,376,740 stalled-cycles-frontend # 1.92% frontend cycles idle ( +- 0.88% ) (49.99%) 300,346,181,651 stalled-cycles-backend # 67.36% backend cycles idle ( +- 0.76% ) (50.01%) 258,091,488,691 instructions # 0.58 insn per cycle # 1.16 stalled cycles per insn ( +- 0.22% ) (66.67%) 70,568,169,256 branches # 673.660 M/sec ( +- 0.17% ) (50.01%) 3,100,725,426 branch-misses # 4.39% of all branches ( +- 0.20% ) (49.99%) 105.583 +- 0.589 seconds time elapsed ( +- 0.56% ) Patched: Performance counter stats for 'drmgr -c mem -a -q 4096' (10 runs): 104,055.69 msec task-clock # 0.993 CPUs utilized ( +- 0.32% ) 4,606 context-switches # 0.044 K/sec ( +- 0.20% ) 2,463 cpu-migrations # 0.024 K/sec ( +- 0.93% ) 394 page-faults # 0.004 K/sec ( +- 0.25% ) 442,951,129,921 cycles # 4.257 GHz ( +- 0.32% ) (66.66%) 8,710,413,329 stalled-cycles-frontend # 1.97% frontend cycles idle ( +- 0.47% ) (50.06%) 299,656,905,836 stalled-cycles-backend # 67.65% backend cycles idle ( +- 0.39% ) (50.02%) 252,731,168,193 instructions # 0.57 insn per cycle # 1.19 stalled cycles per insn ( +- 0.20% ) (66.66%) 68,902,851,121 branches # 662.173 M/sec ( +- 0.13% ) (49.94%) 3,100,242,882 branch-misses # 4.50% of all branches ( +- 0.15% ) (49.98%) 104.829 +- 0.325 seconds time elapsed ( +- 0.31% ) This is consistent. An add-by-count hot-add operation adds LMBs greedily, so LMBs near the start of the drconf range are considered first. On an otherwise idle LPAR with so many LMBs we would expect to find the LMBs we need near the start of the drconf range, hence the smaller speedup. Signed-off-by: Scott Cheloha <cheloha@linux.ibm.com> Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200916145122.3408129-1-cheloha@linux.ibm.com
2020-10-06powerpc/rtas: Restrict RTAS requests from userspaceAndrew Donnellan2-0/+166
A number of userspace utilities depend on making calls to RTAS to retrieve information and update various things. The existing API through which we expose RTAS to userspace exposes more RTAS functionality than we actually need, through the sys_rtas syscall, which allows root (or anyone with CAP_SYS_ADMIN) to make any RTAS call they want with arbitrary arguments. Many RTAS calls take the address of a buffer as an argument, and it's up to the caller to specify the physical address of the buffer as an argument. We allocate a buffer (the "RMO buffer") in the Real Memory Area that RTAS can access, and then expose the physical address and size of this buffer in /proc/powerpc/rtas/rmo_buffer. Userspace is expected to read this address, poke at the buffer using /dev/mem, and pass an address in the RMO buffer to the RTAS call. However, there's nothing stopping the caller from specifying whatever address they want in the RTAS call, and it's easy to construct a series of RTAS calls that can overwrite arbitrary bytes (even without /dev/mem access). Additionally, there are some RTAS calls that do potentially dangerous things and for which there are no legitimate userspace use cases. In the past, this would not have been a particularly big deal as it was assumed that root could modify all system state freely, but with Secure Boot and lockdown we need to care about this. We can't fundamentally change the ABI at this point, however we can address this by implementing a filter that checks RTAS calls against a list of permitted calls and forces the caller to use addresses within the RMO buffer. The list is based off the list of calls that are used by the librtas userspace library, and has been tested with a number of existing userspace RTAS utilities. For compatibility with any applications we are not aware of that require other calls, the filter can be turned off at build time. Cc: stable@vger.kernel.org Reported-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200820044512.7543-1-ajd@linux.ibm.com
2020-10-06powerpc/perf: Exclude pmc5/6 from the irrelevant PMU group constraintsAthira Rajeev1-0/+10
PMU counter support functions enforces event constraints for group of events to check if all events in a group can be monitored. Incase of event codes using PMC5 and PMC6 ( 500fa and 600f4 respectively ), not all constraints are applicable, say the threshold or sample bits. But current code includes pmc5 and pmc6 in some group constraints (like IC_DC Qualifier bits) which is actually not applicable and hence results in those events not getting counted when scheduled along with group of other events. Patch fixes this by excluding PMC5/6 from constraints which are not relevant for it. Fixes: 7ffd948 ("powerpc/perf: factor out power8 pmu functions") Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com> Reviewed-by: Madhavan Srinivasan <maddy@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/1600672204-1610-1-git-send-email-atrajeev@linux.vnet.ibm.com
2020-10-06powerpc/smp: Optimize update_coregroup_maskSrikar Dronamraju1-8/+22
All threads of a SMT4/SMT8 core can either be part of CPU's coregroup mask or outside the coregroup. Use this relation to reduce the number of iterations needed to find all the CPUs that share the same coregroup Use a temporary mask to iterate through the CPUs that may share coregroup mask. Also instead of setting one CPU at a time into cpu_coregroup_mask, copy the SMT4/SMT8/submask at one shot. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200921095653.9701-12-srikar@linux.vnet.ibm.com
2020-10-06powerpc/smp: Move coregroup mask updation to a new functionSrikar Dronamraju1-13/+19
Move the logic for updating the coregroup mask of a CPU to its own function. This will help in reworking the updation of coregroup mask in subsequent patch. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200921095653.9701-11-srikar@linux.vnet.ibm.com
2020-10-06powerpc/smp: Optimize update_mask_by_l2Srikar Dronamraju1-6/+45
All threads of a SMT4 core can either be part of this CPU's l2-cache mask or not related to this CPU l2-cache mask. Use this relation to reduce the number of iterations needed to find all the CPUs that share the same l2-cache. Use a temporary mask to iterate through the CPUs that may share l2_cache mask. Also instead of setting one CPU at a time into cpu_l2_cache_mask, copy the SMT4/sub mask at one shot. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200921095653.9701-10-srikar@linux.vnet.ibm.com
2020-10-06powerpc/smp: Check for duplicate topologies and consolidateSrikar Dronamraju1-0/+26
CACHE and COREGROUP domains are now part of default topology. However on systems that don't support CACHE or COREGROUP, these domains will eventually be degenerated. The degeneration happens per CPU. Do note the current fixup_topology() logic ensures that mask of a domain that is not supported on the current platform is set to the previous domain. Instead of waiting for the scheduler to degenerated try to consolidate based on their masks and sd_flags. This is done just before setting the scheduler topology. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200921095653.9701-9-srikar@linux.vnet.ibm.com
2020-10-06powerpc/smp: Depend on cpu_l1_cache_map when adding CPUsSrikar Dronamraju1-4/+3
Currently on hotplug/hotunplug, CPU iterates through all the CPUs in its core to find threads in its thread group. However this info is already captured in cpu_l1_cache_map. Hence reduce iterations and cleanup add_cpu_to_smallcore_masks function. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200921095653.9701-8-srikar@linux.vnet.ibm.com
2020-10-06powerpc/smp: Stop passing mask to update_mask_by_l2Srikar Dronamraju1-4/+4
update_mask_by_l2 is called only once. But it passes cpu_l2_cache_mask as parameter. Instead of passing cpu_l2_cache_mask, use it directly in update_mask_by_l2. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200921095653.9701-7-srikar@linux.vnet.ibm.com
2020-10-06powerpc/smp: Limit CPUs traversed to within a node.Srikar Dronamraju1-1/+1
All the arch specific topology cpumasks are within a node/DIE. However when setting these per CPU cpumasks, system traverses through all the online CPUs. This is redundant. Reduce the traversal to only CPUs that are online in the node to which the CPU belongs to. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200921095653.9701-6-srikar@linux.vnet.ibm.com
2020-10-06powerpc/smp: Optimize remove_cpu_from_masksSrikar Dronamraju1-2/+9
While offlining a CPU, system currently iterate through all the CPUs in the DIE to clear sibling, l2_cache and smallcore maps. However if there are more cores in a DIE, system can end up spending more time iterating through CPUs which are completely unrelated. Optimize this by only iterating through smaller but relevant cpumap. If shared_cache is set, cpu_l2_cache_map should be relevant else cpu_sibling_map would be relevant. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200921095653.9701-5-srikar@linux.vnet.ibm.com
2020-10-06powerpc/smp: Remove get_physical_package_idSrikar Dronamraju2-25/+0
Now that cpu_core_mask has been removed and topology_core_cpumask has been updated to use cpu_cpu_mask, we no more need get_physical_package_id. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200921095653.9701-4-srikar@linux.vnet.ibm.com
2020-10-06powerpc/smp: Stop updating cpu_core_maskSrikar Dronamraju2-31/+7
Anton Blanchard reported that his 4096 vcpu KVM guest took around 30 minutes to boot. He also analyzed it to the time taken to iterate while setting the cpu_core_mask. Further analysis shows that cpu_core_mask and cpu_cpu_mask for any CPU would be equal on Power. However updating cpu_core_mask took forever to update as its a per cpu cpumask variable. Instead cpu_cpu_mask was a per NODE /per DIE cpumask that was shared by all the respective CPUs. Also cpu_cpu_mask is needed from a scheduler perspective. However cpu_core_map is an exported symbol. Hence stop updating cpu_core_map and make it point to cpu_cpu_mask. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200921095653.9701-3-srikar@linux.vnet.ibm.com
2020-10-06powerpc/topology: Update topology_core_cpumaskSrikar Dronamraju1-1/+1
On Power, cpu_core_mask and cpu_cpu_mask refer to the same set of CPUs. cpu_cpu_mask is needed by scheduler, hence look at deprecating cpu_core_mask. Before deleting the cpu_core_mask, ensure its only user is moved to cpu_cpu_mask. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200921095653.9701-2-srikar@linux.vnet.ibm.com
2020-10-06powerpc/tm: Save and restore AMR on treclaim and trechkptGustavo Romero3-4/+33
Althought AMR is stashed in the checkpoint area, currently we don't save it to the per thread checkpoint struct after a treclaim and so we don't restore it either from that struct when we trechkpt. As a consequence when the transaction is later rolled back the kernel space AMR value when the trechkpt was done appears in userspace. That commit saves and restores AMR accordingly on treclaim and trechkpt. Since AMR value is also used in kernel space in other functions, it also takes care of stashing kernel live AMR into the stack before treclaim and before trechkpt, restoring it later, just before returning from tm_reclaim and __tm_recheckpoint. Is also fixes two nonrelated comments about CR and MSR. Signed-off-by: Gustavo Romero <gromero@linux.ibm.com> Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200919150025.9609-1-gromero@linux.ibm.com
2020-10-06powerpc/eeh: Clean up PE addressingOliver O'Halloran5-93/+17
When support for EEH on PowerNV was added a lot of pseries specific code was made "generic" and some of the quirks of pseries EEH came along for the ride. One of the stranger quirks is eeh_pe containing two types of PE address: pe->addr and pe->config_addr. There reason for this appears to be historical baggage rather than any real requirements. On pseries EEH PEs are manipulated using RTAS calls. Each EEH RTAS call takes a "PE configuration address" as an input which is used to identify which EEH PE is being manipulated by the call. When initialising the EEH state for a device the first thing we need to do is determine the configuration address for the PE which contains the device so we can enable EEH on that PE. This process is outlined in PAPR which is the modern (i.e post-2003) FW specification for pseries. However, EEH support was first described in the pSeries RISC Platform Architecture (RPA) and although they are mostly compatible EEH is one of the areas where they are not. The major difference is that RPA doesn't actually have the concept of a PE. On RPA systems the EEH RTAS calls are done on a per-device basis using the same config_addr that would be passed to the RTAS functions to access PCI config space (e.g. ibm,read-pci-config). The config_addr is not identical since the function and config register offsets of the config_addr must be set to zero. EEH operations being done on a per-device basis doesn't make a whole lot of sense when you consider how EEH was implemented on legacy PCI systems. For legacy PCI(-X) systems EEH was implemented using special PCI-PCI bridges which contained logic to detect errors and freeze the secondary bus when one occurred. This means that the EEH enabled state is shared among all devices behind that EEH bridge. As a result there's no way to implement the per-device control required for the semantics specified by RPA. It can be made to work if we assume that a separate EEH bridge exists for each EEH capable PCI slot and there are no bridges behind those slots. However, RPA also specifies the ibm,configure-bridge RTAS call for re-initalising bridges behind EEH capable slots after they are reset due to an EEH event so that is probably not a valid assumption. This incoherence was fixed in later PAPR, which succeeded RPA. Unfortunately, since Linux EEH support seems to have been implemented based on the RPA spec some of the legacy assumptions were carried over (probably for POWER4 compatibility). The fix made in PAPR was the introduction of the "PE" concept and redefining the EEH RTAS calls (set-eeh-option, reset-slot, etc) to operate on a per-PE basis so all devices behind an EEH bride would share the same EEH state. The "config_addr" argument to the EEH RTAS calls became the "PE_config_addr" and the OS was required to use the ibm,get-config-addr-info RTAS call to find the correct PE address for the device. When support for the new interfaces was added to Linux it was implemented using something like: At probe time: pdn->eeh_config_addr = rtas_config_addr(pdn); pdn->eeh_pe_config_addr = rtas_get_config_addr_info(pdn); When performing an RTAS call: config_addr = pdn->eeh_config_addr; if (pdn->eeh_pe_config_addr) config_addr = pdn->eeh_pe_config_addr; rtas_call(..., config_addr, ...); In other words, if the ibm,get-config-addr-info RTAS call is implemented and returned a valid result we'd use that as the argument to the EEH RTAS calls. If not, Linux would fall back to using the device's config_addr. Over time these addresses have moved around going from pci_dn to eeh_dev and finally into eeh_pe. Today the users look like this: config_addr = pe->config_addr; if (pe->addr) config_addr = pe->addr; rtas_call(..., config_addr, ...); However, considering the EEH core always operates on a per-PE basis and even on pseries the only per-device operation is the initial call to ibm,set-eeh-option I'm not sure if any of this actually works on an RPA system today. It doesn't make much sense to have the fallback address in a generic structure either since the bulk of the code which reference it is in pseries anyway. The EEH core makes a token effort to support looking up a PE using the config_addr by having two arguments to eeh_pe_get(). However, a survey of all the callers to eeh_pe_get() shows that all bar one have the config_addr argument hard-coded to zero.The only caller that doesn't is in eeh_pe_tree_insert() which has: if (!eeh_has_flag(EEH_VALID_PE_ZERO) && !edev->pe_config_addr) return -EINVAL; pe = eeh_pe_get(hose, edev->pe_config_addr, edev->bdfn); The third argument (config_addr) is only used if the second (pe->addr) argument is invalid. The preceding check ensures that the call to eeh_pe_get() will never happen if edev->pe_config_addr is invalid so there is no situation where eeh_pe_get() will search for a PE based on the 3rd argument. The check also means that we'll never insert a PE into the tree where pe_config_addr is zero since EEH_VALID_PE_ZERO is never set on pseries. All the users of the fallback address on pseries never actually use the fallback and all the only caller that supplies something for the config_addr argument to eeh_pe_get() never use it either. It's all dead code. This patch removes the fallback address from eeh_pe since nothing uses it. Specificly, we do this by: 1) Removing pe->config_addr 2) Removing the EEH_VALID_PE_ZERO flag 3) Removing the fallback address argument to eeh_pe_get(). 4) Removing all the checks for pe->addr being zero in the pseries EEH code. This leaves us with PE's only being identified by what's in their pe->addr field and the EEH core relying on the platform to ensure that eeh_dev's are only inserted into the EEH tree if they're actually inside a PE. No functional changes, I hope. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200918093050.37344-9-oohall@gmail.com