kernel.git/arch/powerpc/kernel/asm-offsets.c, branch linux-6.10.y

powerpc/vdso: Fix VDSO data access when running in a non-root time namespace

2024-10-10T10:00:44Z

[ Upstream commit c73049389e58c01e2e3bbfae900c8daeee177191 ] When running in a non-root time namespace, the global VDSO data page is replaced by a dedicated namespace data page and the global data page is mapped next to it. Detailed explanations can be found at commit 660fd04f9317 ("lib/vdso: Prepare for time namespace support"). When it happens, __kernel_get_syscall_map and __kernel_get_tbfreq and __kernel_sync_dicache don't work anymore because they read 0 instead of the data they need. To address that, clock_mode has to be read. When it is set to VDSO_CLOCKMODE_TIMENS, it means it is a dedicated namespace data page and the global data is located on the following page. Add a macro called get_realdatapage which reads clock_mode and add PAGE_SIZE to the pointer provided by get_datapage macro when clock_mode is equal to VDSO_CLOCKMODE_TIMENS. Use this new macro instead of get_datapage macro except for time functions as they handle it internally. Fixes: 74205b3fc2ef ("powerpc/vdso: Add support for time namespaces") Reported-by: Jason A. Donenfeld Closes: https://lore.kernel.org/all/ZtnYqZI-nrsNslwy@zx2c4.com/ Signed-off-by: Christophe Leroy Acked-by: Michael Ellerman Signed-off-by: Jason A. Donenfeld Signed-off-by: Sasha Levin

powerpc: Remove duplicate/unnecessary ifdefs

2024-02-21T04:15:40Z

When an ifdef is used in the below manner, second one could be considered as duplicate. ifdef DEFINE_A ...code block... ifdef DEFINE_A <-- This is a duplicate. ...code block... endif else ifndef DEFINE_A <-- This is also duplicate. ...code block... endif endif More details about the script and methods used to find these code patterns are in cover letter of [1]. Few places in arch/powerpc where this pattern was seen: paca.h: Hunk1: Code is under check of CONFIG_PPC64 from line 13, hence the second CONFIG_PPC64 at line 166 is a duplicate. Hunk2: CONFIG_PPC_BOOK3S_64 was defined back to back. Merged the two ifdefs. asm-offsets.c: Code is under check of CONFIG_PPC64 from line 176 hence second CONFIG_PPC64 at line 249 is a duplicate. powermac/feature.c: #ifndef CONFIG_PPC64 is used at line 2066. And then in #else again #ifdef CONFIG_PPC64 is used. Which is a duplicate since in #else means CONFIG_PPC64 is defined. xmon.c: Code is under the check of CONFIG_SMP from line 521 hence the same check of CONFIG_SMP at line 646 is a duplicate. No functional change is intended here. It only aims to improve code readability. [1] https://lore.kernel.org/all/20240118080326.13137-1-sshegde@linux.ibm.com/ Signed-off-by: Shrikanth Hegde Signed-off-by: Michael Ellerman Link: https://msgid.link/20240216053016.528906-1-sshegde@linux.ibm.com

powerpc/64: vmlinux support building with PCREL addresing

2023-04-20T02:59:21Z

PC-Relative or PCREL addressing is an extension to the ELF ABI which uses Power ISA v3.1 PC-relative instructions to calculate addresses, rather than the traditional TOC scheme. Add an option to build vmlinux using pcrel addressing. Modules continue to use TOC addressing. - TOC address helpers and r2 are poisoned with -1 when running vmlinux. r2 could be used for something useful once things are ironed out. - Assembly must call C functions with @notoc annotation, or the linker complains aobut a missing nop after the call. This is done with the CFUNC macro introduced earlier. - Boot: with the exception of prom_init, the execution branches to the kernel virtual address early in boot, before any addresses are generated, which ensures 34-bit pcrel addressing does not miss the high PAGE_OFFSET bits. TOC relative addressing has a similar requirement. prom_init does not go to the virtual address and its addresses should not carry over to the post-prom kernel. - Ftrace trampolines are converted from TOC addressing to pcrel addressing, including module ftrace trampolines that currently use the kernel TOC to find ftrace target functions. - BPF function prologue and function calling generation are converted from TOC to pcrel. - copypage_64.S has an interesting problem, prefixed instructions have alignment restrictions so the linker can add padding, which makes the assembler treat the difference between two local labels as non-constant even if alignment is arranged so padding is not required. This may need toolchain help to solve nicely, for now move the prefix instruction out of the alternate patch section to work around it. This reduces kernel text size by about 6%. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://msgid.link/20230408021752.862660-6-npiggin@gmail.com

powerpc: add a define for the switch frame size and regs offset

2022-12-02T06:54:08Z

This is open-coded in process.c, ppc32 uses a different define with the same value, and the C definition is name differently which makes it an extra indirection to grep for. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20221127124942.1665522-12-npiggin@gmail.com

powerpc: add definition for pt_regs offset within an interrupt frame

2022-12-02T06:54:08Z

This is a common offset that currently uses the overloaded STACK_FRAME_OVERHEAD constant. It's easier to read and more flexible to use a specific regs offset for this. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20221127124942.1665522-8-npiggin@gmail.com

powerpc/kvm: Remove unused macros from asm-offset

2022-11-24T12:31:47Z

The kvm code was refactored to convert some of kvm assembly routines to C. This includes commits which moved code path for the kvm guest entry/exit for p7/8 from aseembly to C. As part of the code changes, usage of some of the macros were removed. But definitions still exist in the assembly files. Commits are listed below: Commit 2e1ae9cd56f8 ("KVM: PPC: Book3S HV: Implement radix prefetch workaround by disabling MMU") Commit 9769a7fd79b6 ("KVM: PPC: Book3S HV: Remove radix guest support from P7/8 path") Commit fae5c9f3664b ("KVM: PPC: Book3S HV: remove ISA v3.0 and v3.1 support from P7/8 path") Commit 57dc0eed73ca ("KVM: PPC: Book3S HV P9: Implement PMU save/restore in C") Many of the asm-offset macro definitions were missed to remove. Patch fixes by removing the unused macros. Signed-off-by: Disha Goel Reviewed-by: Nicholas Piggin Reviewed-by: Athira Rajeev Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220916105736.268153-2-disgoel@linux.vnet.ibm.com

powerpc: Remove CONFIG_PPC_FSL_BOOK3E

2022-09-26T13:00:13Z

CONFIG_PPC_FSL_BOOK3E is redundant with CONFIG_PPC_E500. Remove it. And rename five files accordingly. Signed-off-by: Christophe Leroy [mpe: Rename include guards to match new file names] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/795cb93b88c9a0279289712e674f39e3b108a1b4.1663606876.git.christophe.leroy@csgroup.eu

powerpc: Remove CONFIG_PPC_BOOK3E

2022-09-26T13:00:13Z

CONFIG_PPC_BOOK3E is redundant with CONFIG_PPC_BOOK3E_64. The later is more explicit about the fact that it's a 64 bits target. Remove CONFIG_PPC_BOOK3E. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/5d0891490813c19cdcfc04678f512ea68cba3e64.1663606876.git.christophe.leroy@csgroup.eu

KVM: PPC: Book3S HV: Add a new config for P8 debug timing

2022-06-29T09:21:21Z

Turn the existing Kconfig KVM_BOOK3S_HV_EXIT_TIMING into KVM_BOOK3S_HV_P8_TIMING in preparation for the addition of a new config for P9 timings. This applies only to P8 code, the generic timing code is still kept under KVM_BOOK3S_HV_EXIT_TIMING. Signed-off-by: Fabiano Rosas Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220525130554.2614394-3-farosas@linux.ibm.com

powerpc/ftrace: Add support for livepatch to PPC32

2022-02-07T10:03:10Z

PPC64 needs some special logic to properly set up the TOC. See commit 85baa095497f ("powerpc/livepatch: Add live patching support on ppc64le") for details. PPC32 doesn't have TOC so it doesn't need that logic, so adding LIVEPATCH support is straight forward. Add CONFIG_LIVEPATCH_64 and move livepatch stack logic into that item. Livepatch sample modules all work. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/63cb094125b6a6038c65eeac2abaabbabe63addd.1640017960.git.christophe.leroy@csgroup.eu