#
0f71dcfb |
|
19-Jun-2023 |
Naveen N Rao <naveen@kernel.org> |
powerpc/ftrace: Add support for -fpatchable-function-entry GCC v13.1 updated support for -fpatchable-function-entry on ppc64le to emit nops after the local entry point, rather than before it. This allows us to use this in the kernel for ftrace purposes. A new script is added under arch/powerpc/tools/ to help detect if nops are emitted after the function local entry point, or before the global entry point. With -fpatchable-function-entry, we no longer have the profiling instructions generated at function entry, so we only need to validate the presence of two nops at the ftrace location in ftrace_init_nop(). We patch the preceding instruction with 'mflr r0' to match the -mprofile-kernel ABI for subsequent ftrace use. This changes the profiling instructions used on ppc32. The default -pg option emits an additional 'stw' instruction after 'mflr r0' and before the branch to _mcount 'bl _mcount'. This is very similar to the original -mprofile-kernel implementation on ppc64le, where an additional 'std' instruction was used to save LR to its save location in the caller's stackframe. Subsequently, this additional store was removed in later compiler versions for performance reasons. The same reasons apply for ppc32 so we only patch in a 'mflr r0'. Signed-off-by: Naveen N Rao <naveen@kernel.org> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/68586d22981a2c3bb45f27a2b621173d10a7d092.1687166935.git.naveen@kernel.org
|
#
77e69ee7 |
|
07-Apr-2023 |
Nicholas Piggin <npiggin@gmail.com> |
powerpc/64: modules support building with PCREL addresing Build modules using PCREL addressing when CONFIG_PPC_KERNEL_PCREL=y. - The module loader must handle several new relocation types: * R_PPC64_REL24_NOTOC is a function call handled like R_PPC_REL24, but does not restore r2 upon return. The external function call stub is changed to use pcrel addressing to load the function pointer rather than based on the module TOC. * R_PPC64_GOT_PCREL34 is a reference to external data. A GOT table must be built by hand, because the linker adds this during the final link (which is not done for kernel modules). The GOT table is built similarly to the way the external function call stub table is. This section is called .mygot because .got has a special meaning for the linker and can become upset. * R_PPC64_PCREL34 is used for local data addressing, but there is a special case where the percpu section is moved at load-time to the percpu area which is out of range of this relocation. This requires the PCREL34 relocations are converted to use GOT_PCREL34 addressing. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Some coding style & formatting fixups] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230408021752.862660-7-npiggin@gmail.com
|
#
7e3a68be |
|
07-Apr-2023 |
Nicholas Piggin <npiggin@gmail.com> |
powerpc/64: vmlinux support building with PCREL addresing 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 <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230408021752.862660-6-npiggin@gmail.com
|
#
37251c71 |
|
24-Jan-2023 |
Josh Poimboeuf <jpoimboe@kernel.org> |
powerpc/module_64: Fix "expected nop" error on module re-patching When a module with a livepatched function is unloaded and then reloaded, klp attempts to dynamically re-patch it. On ppc64, that fails with the following error: module_64: livepatch_nfsd: Expected nop after call, got e8410018 at e_show+0x60/0x548 [livepatch_nfsd] livepatch: failed to initialize patch 'livepatch_nfsd' for module 'nfsd' (-8) livepatch: patch 'livepatch_nfsd' failed for module 'nfsd', refusing to load module 'nfsd' The error happens because the restore r2 instruction had already previously been written into the klp module's replacement function when the original function was patched the first time. So the instruction wasn't a nop as expected. When the restore r2 instruction has already been patched in, detect that and skip the warning and the instruction write. Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Reviewed-by: Petr Mladek <pmladek@suse.com> Acked-by: Song Liu <song@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/2f6329ffd9674df6ff57e03edeb2ca54414770ab.1674617130.git.jpoimboe@kernel.org
|
#
bc2c6f56 |
|
24-Jan-2023 |
Josh Poimboeuf <jpoimboe@kernel.org> |
powerpc/module_64: Improve restore_r2() return semantics restore_r2() returns 1 on success, which is surprising for a non-boolean function. Change it to return 0 on success and -errno on error to match kernel coding convention. Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Reviewed-by: Petr Mladek <pmladek@suse.com> Acked-by: Song Liu <song@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/15baf76c271a0ae09f7b8556e50f2b4251e7049d.1674617130.git.jpoimboe@kernel.org
|
#
de3d098d |
|
27-Nov-2022 |
Nicholas Piggin <npiggin@gmail.com> |
powerpc/64: Add module check for ELF ABI version Override the generic module ELF check to provide a check for the ELF ABI version. This becomes important if we allow big-endian ELF ABI V2 builds but it doesn't hurt to check now. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20221128041539.1742489-3-npiggin@gmail.com
|
#
e0c2ef43 |
|
08-May-2022 |
Christophe Leroy <christophe.leroy@csgroup.eu> |
powerpc/modules: Use PPC_LI macros instead of opencoding Use PPC_LI_MASK and PPC_LI() instead of opencoding. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/3d56d7bc3200403773d54e62659d0e01292a055d.1652074503.git.christophe.leroy@csgroup.eu
|
#
7d40aff8 |
|
08-May-2022 |
Christophe Leroy <christophe.leroy@csgroup.eu> |
powerpc: Replace PPC64_ELF_ABI_v{1/2} by CONFIG_PPC64_ELF_ABI_V{1/2} Replace all uses of PPC64_ELF_ABI_v1 and PPC64_ELF_ABI_v2 by resp CONFIG_PPC64_ELF_ABI_V1 and CONFIG_PPC64_ELF_ABI_V2. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/ba13d59e8c50bc9aa6328f1c7f0c0d0278e0a3a7.1652074503.git.christophe.leroy@csgroup.eu
|
#
1fd02f66 |
|
30-Apr-2022 |
Julia Lawall <Julia.Lawall@inria.fr> |
powerpc: fix typos in comments Various spelling mistakes in comments. Detected with the help of Coccinelle. Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr> Reviewed-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220430185654.5855-1-Julia.Lawall@inria.fr
|
#
8a0edc72 |
|
23-Feb-2022 |
Guo Zhengkui <guozhengkui@vivo.com> |
powerpc/module_64: fix array_size.cocci warning Fix following coccicheck warning: ./arch/powerpc/kernel/module_64.c:432:40-41: WARNING: Use ARRAY_SIZE. ARRAY_SIZE(arr) is a macro provided by the kernel. It makes sure that arr is an array, so it's safer than sizeof(arr) / sizeof(arr[0]) and more standard. Signed-off-by: Guo Zhengkui <guozhengkui@vivo.com> Reviewed-by: Russell Currey <ruscur@russell.cc> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220223075426.20939-1-guozhengkui@vivo.com
|
#
0dc690e4 |
|
15-Feb-2022 |
Christophe Leroy <christophe.leroy@csgroup.eu> |
asm-generic: Define 'func_desc_t' to commonly describe function descriptors We have three architectures using function descriptors, each with its own type and name. Add a common typedef that can be used in generic code. Also add a stub typedef for architecture without function descriptors, to avoid a forest of #ifdefs. It replaces the similar 'func_desc_t' previously defined in arch/powerpc/kernel/module_64.c Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Helge Deller <deller@gmx.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/f1f91b142b3c1082bdc1586ce71c9bac1e75213c.1644928018.git.christophe.leroy@csgroup.eu
|
#
2fd98637 |
|
15-Feb-2022 |
Christophe Leroy <christophe.leroy@csgroup.eu> |
powerpc: Prepare func_desc_t for refactorisation In preparation of making func_desc_t generic, change the ELFv2 version to a struct containing 'addr' element. This allows using single helpers common to ELFv1 and ELFv2 and reduces the amount of #ifdef's Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/5c36105e08b27b98450535bff48d71b690c19739.1644928018.git.christophe.leroy@csgroup.eu
|
#
d3e32b99 |
|
15-Feb-2022 |
Christophe Leroy <christophe.leroy@csgroup.eu> |
powerpc: Use 'struct func_desc' instead of 'struct ppc64_opd_entry' 'struct ppc64_opd_entry' is somehow redundant with 'struct func_desc', the later is more correct/complete as it includes the third field which is unused. So use 'struct func_desc' instead of 'struct ppc64_opd_entry' Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/34e76bac6cbe95a63ecd37df69fb7feb93b0ea7c.1644928018.git.christophe.leroy@csgroup.eu
|
#
d4be60fe |
|
01-Feb-2022 |
Wedson Almeida Filho <wedsonaf@google.com> |
powerpc/module_64: use module_init_section instead of patching names Without this patch, module init sections are disabled by patching their names in arch-specific code when they're loaded (which prevents code in layout_sections from finding init sections). This patch uses the new arch-specific module_init_section instead. This allows modules that have .init_array sections to have the initialisers properly called (on load, before init). Without this patch, the initialisers are not called because .init_array is renamed to _init_array, and thus isn't found by code in find_module_sections(). Signed-off-by: Wedson Almeida Filho <wedsonaf@google.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220202055123.2144842-1-wedsonaf@google.com
|
#
8734b41b |
|
23-Nov-2021 |
Russell Currey <ruscur@russell.cc> |
powerpc/module_64: Fix livepatching for RO modules Livepatching a loaded module involves applying relocations through apply_relocate_add(), which attempts to write to read-only memory when CONFIG_STRICT_MODULE_RWX=y. Work around this by performing these writes through the text poke area by using patch_instruction(). R_PPC_REL24 is the only relocation type generated by the kpatch-build userspace tool or klp-convert kernel tree that I observed applying a relocation to a post-init module. A more comprehensive solution is planned, but using patch_instruction() for R_PPC_REL24 on should serve as a sufficient fix. This does have a performance impact, I observed ~15% overhead in module_load() on POWER8 bare metal with checksum verification off. Fixes: c35717c71e98 ("powerpc: Set ARCH_HAS_STRICT_MODULE_RWX") Cc: stable@vger.kernel.org # v5.14+ Reported-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Russell Currey <ruscur@russell.cc> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> [mpe: Check return codes from patch_instruction()] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211214121248.777249-1-mpe@ellerman.id.au
|
#
47b04699 |
|
20-May-2021 |
Christophe Leroy <christophe.leroy@csgroup.eu> |
powerpc/modules: Use PPC_RAW_xx() macros To improve readability, use PPC_RAW_xx() macros instead of open coding. Those macros are self-explanatory so the comments can go as well. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/99d9ee8849d3992beeadb310a665aae01c3abfb1.1621506159.git.christophe.leroy@csgroup.eu
|
#
fe557319 |
|
17-Jun-2020 |
Christoph Hellwig <hch@lst.de> |
maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault Better describe what these functions do. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
bd55e792 |
|
21-Apr-2020 |
Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> |
powerpc/module_64: Use special stub for _mcount() with -mprofile-kernel Since commit c55d7b5e64265f ("powerpc: Remove STRICT_KERNEL_RWX incompatibility with RELOCATABLE"), powerpc kernels with -mprofile-kernel can crash in certain scenarios with a trace like below: BUG: Unable to handle kernel instruction fetch (NULL pointer?) Faulting instruction address: 0x00000000 Oops: Kernel access of bad area, sig: 11 [#1] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=256 DEBUG_PAGEALLOC NUMA PowerNV <snip> NIP [0000000000000000] 0x0 LR [c0080000102c0048] ext4_iomap_end+0x8/0x30 [ext4] Call Trace: iomap_apply+0x20c/0x920 (unreliable) iomap_bmap+0xfc/0x160 ext4_bmap+0xa4/0x180 [ext4] bmap+0x4c/0x80 jbd2_journal_init_inode+0x44/0x1a0 [jbd2] ext4_load_journal+0x440/0x860 [ext4] ext4_fill_super+0x342c/0x3ab0 [ext4] mount_bdev+0x25c/0x290 ext4_mount+0x28/0x50 [ext4] legacy_get_tree+0x4c/0xb0 vfs_get_tree+0x4c/0x130 do_mount+0xa18/0xc50 sys_mount+0x158/0x180 system_call+0x5c/0x68 The NIP points to NULL, or a random location (data even), while the LR always points to the LEP of a function (with an offset of 8), indicating that something went wrong with ftrace. However, ftrace is not necessarily active when such crashes occur. The kernel OOPS sometimes follows a warning from ftrace indicating that some module functions could not be patched with a nop. Other times, if a module is loaded early during boot, instruction patching can fail due to a separate bug, but the error is not reported due to missing error reporting. In all the above cases when instruction patching fails, ftrace will be disabled but certain kernel module functions will be left with default calls to _mcount(). This is not a problem with ELFv1. However, with -mprofile-kernel, the default stub is problematic since it depends on a valid module TOC in r2. If the kernel (or a different module) calls into a function that does not use the TOC, the function won't have a prologue to setup the module TOC. When that function calls into _mcount(), we will end up in the relocation stub that will use the previous TOC, and end up trying to jump into a random location. From the above trace: iomap_apply+0x20c/0x920 [kernel TOC] | V ext4_iomap_end+0x8/0x30 [no GEP == kernel TOC] | V _mcount() stub [uses kernel TOC -> random entry] To address this, let's change over to using the special stub that is used for ftrace_[regs_]caller() for _mcount(). This ensures that we are not dependent on a valid module TOC in r2 for default _mcount() handling. Reported-by: Qian Cai <cai@lca.pw> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Tested-by: Qian Cai <cai@lca.pw> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/8affd4298d22099bbd82544fab8185700a6222b1.1587488954.git.naveen.n.rao@linux.vnet.ibm.com
|
#
1f2aaed2 |
|
21-Apr-2020 |
Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> |
powerpc/module_64: Simplify check for -mprofile-kernel ftrace relocations For -mprofile-kernel, we need special handling when generating stubs for ftrace calls such as _mcount(). To faciliate this, we check if a R_PPC64_REL24 relocation is for a symbol named "_mcount()" along with also checking the instruction sequence. The latter is not really required since "_mcount()" is an exported symbol and kernel modules cannot use it. As such, drop the additional checking and simplify the code. This helps unify stub creation for ftrace stubs with -mprofile-kernel and aids in code reuse. Also rename is_mprofile_mcount_callsite() to is_mprofile_ftrace_call() to reflect the checking being done. 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/7d9c316adfa1fb787ad268bb4691e7e4059ff2d5.1587488954.git.naveen.n.rao@linux.vnet.ibm.com
|
#
03b51416 |
|
21-Apr-2020 |
Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> |
powerpc/module_64: Consolidate ftrace code module_trampoline_target() is only used by ftrace. Move the prototype within the appropriate #ifdef in the header. Also, move the function body to the end of module_64.c so as to consolidate all ftrace code in one place. No functional changes. 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/2527351f65c53c5866068ae130dc34c5d4ee8ad9.1587488954.git.naveen.n.rao@linux.vnet.ibm.com
|
#
75346251 |
|
05-May-2020 |
Jordan Niethe <jniethe5@gmail.com> |
powerpc: Use a macro for creating instructions from u32s In preparation for instructions having a more complex data type start using a macro, ppc_inst(), for making an instruction out of a u32. A macro is used so that instructions can be used as initializer elements. Currently this does nothing, but it will allow for creating a data type that can represent prefixed instructions. Signed-off-by: Jordan Niethe <jniethe5@gmail.com> [mpe: Change include guard to _ASM_POWERPC_INST_H] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Alistair Popple <alistair@popple.id.au> Link: https://lore.kernel.org/r/20200506034050.24806-7-jniethe5@gmail.com
|
#
bac7ca7b |
|
02-Apr-2019 |
Andrey Abramov <st5pub@yandex.ru> |
powerpc: module_[32|64].c: replace swap function with built-in one Replace relaswap with built-in one, because relaswap does a simple byte to byte swap. Since Spectre mitigations have made indirect function calls more expensive, and the default simple byte copies swap is implemented without them, an "optimized" custom swap function is now a waste of time as well as code. Signed-off-by: Andrey Abramov <st5pub@yandex.ru> Reviewed-by: George Spelvin <lkml@sdf.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/994931554238042@iva8-b333b7f98ab0.qloud-c.yandex.net
|
#
a2b6f26c |
|
03-May-2019 |
Christophe Leroy <christophe.leroy@c-s.fr> |
powerpc/module64: Use symbolic instructions names. To increase readability/maintainability, replace hard coded instructions values by symbolic names. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> [mpe: Fix R_PPC64_ENTRY case, the addi reads from r2 not r12] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
#
7f9c929a |
|
03-May-2019 |
Christophe Leroy <christophe.leroy@c-s.fr> |
powerpc: Move PPC_HA() PPC_HI() and PPC_LO() to ppc-opcode.h PPC_HA() PPC_HI() and PPC_LO() macros are nice macros. Move them from module64.c to ppc-opcode.h in order to use them in other places. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> [mpe: Clean up formatting in new code, drop duplicates in ftrace.c] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
#
2fb0a2c9 |
|
05-Jul-2019 |
Michael Ellerman <mpe@ellerman.id.au> |
powerpc/module64: Fix comment in R_PPC64_ENTRY handling The comment here is wrong, the addi reads from r2 not r12. The code is correct, 0x38420000 = addi r2,r2,0. Fixes: a61674bdfc7c ("powerpc/module: Handle R_PPC64_ENTRY relocations") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
#
1a59d1b8 |
|
27-May-2019 |
Thomas Gleixner <tglx@linutronix.de> |
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1334 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
#
b851ba02 |
|
29-Aug-2018 |
Nicholas Piggin <npiggin@gmail.com> |
powerpc/64/module: REL32 relocation range check The recent module relocation overflow crash demonstrated that we have no range checking on REL32 relative relocations. This patch implements a basic check, the same kernel that previously oopsed and rebooted now continues with some of these errors when loading the module: module_64: x_tables: REL32 527703503449812 out of range! Possibly other relocations (ADDR32, REL16, TOC16, etc.) should also have overflow checks. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
#
59fe7eaf |
|
28-May-2018 |
Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> |
powerpc64/module elfv1: Set opd addresses after module relocation module_frob_arch_sections() is called before the module is moved to its final location. The function descriptor section addresses we are setting here are thus invalid. Fix this by processing opd section during module_finalize() Fixes: 5633e85b2c313 ("powerpc64: Add .opd based function descriptor dereference") Cc: stable@vger.kernel.org # v4.16 Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
#
abba7597 |
|
30-May-2018 |
Nicholas Piggin <npiggin@gmail.com> |
powerpc/kbuild: move -mprofile-kernel check to Kconfig This eliminates the workaround that requires disabling -mprofile-kernel by default in Kconfig. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
|
#
8ce621e1 |
|
24-May-2018 |
Josh Poimboeuf <jpoimboe@redhat.com> |
powerpc/modules: remove unused mod_arch_specific.toc field The toc field in the mod_arch_specific struct isn't actually used anywhere, so remove it. Also the ftrace-specific fields are now common between 32-bit and 64-bit, so simplify the struct definition a bit by moving them out of the __powerpc64__ #ifdef. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Reviewed-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
#
ae30cc05 |
|
18-Apr-2018 |
Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> |
powerpc64/ftrace: Implement support for ftrace_regs_caller() With -mprofile-kernel, we always save the full register state in ftrace_caller(). While this works, this is inefficient if we're not interested in the register state, such as when we're using the function tracer. Rename the existing ftrace_caller() as ftrace_regs_caller() and provide a simpler implementation for ftrace_caller() that is used when registers are not required to be saved. Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
#
250122ba |
|
18-Apr-2018 |
Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> |
powerpc64/module: Tighten detection of mcount call sites with -mprofile-kernel For R_PPC64_REL24 relocations, we suppress emitting instructions for TOC load/restore in the relocation stub if the relocation is for _mcount() call when using -mprofile-kernel ABI. To detect this, we check if the preceding instructions are per the standard set of instructions emitted by gcc: either the two instruction sequence of 'mflr r0; std r0,16(r1)', or the more optimized variant of a single 'mflr r0'. This is not sufficient since nothing prevents users from hand coding sequences involving a 'mflr r0' followed by a 'bl'. For removing the toc save instruction from the stub, we additionally check if the symbol is "_mcount". Add the same check here as well. Also rename is_early_mcount_callsite() to is_mprofile_mcount_callsite() since that is what is being checked. The use of "early" is misleading since there is nothing involving this function that qualifies as early. Fixes: 153086644fd1f ("powerpc/ftrace: Add support for -mprofile-kernel ftrace ABI") Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
#
5633e85b |
|
09-Nov-2017 |
Sergey Senozhatsky <sergey.senozhatsky@gmail.com> |
powerpc64: Add .opd based function descriptor dereference We are moving towards separate kernel and module function descriptor dereference callbacks. This patch enables it for powerpc64. For pointers that belong to the kernel - Added __start_opd and __end_opd pointers, to track the kernel .opd section address range; - Added dereference_kernel_function_descriptor(). Now we will dereference only function pointers that are within [__start_opd, __end_opd); For pointers that belong to a module - Added dereference_module_function_descriptor() to handle module function descriptor dereference. Now we will dereference only pointers that are within [module->opd.start, module->opd.end). Link: http://lkml.kernel.org/r/20171109234830.5067-4-sergey.senozhatsky@gmail.com To: Tony Luck <tony.luck@intel.com> To: Fenghua Yu <fenghua.yu@intel.com> To: Helge Deller <deller@gmx.de> To: Benjamin Herrenschmidt <benh@kernel.crashing.org> To: Paul Mackerras <paulus@samba.org> To: Michael Ellerman <mpe@ellerman.id.au> To: James Bottomley <jejb@parisc-linux.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Jessica Yu <jeyu@kernel.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: linux-ia64@vger.kernel.org Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-kernel@vger.kernel.org Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Tested-by: Santosh Sivaraj <santosh@fossix.org> #powerpc Signed-off-by: Petr Mladek <pmladek@suse.com>
|
#
5c45b528 |
|
06-Dec-2017 |
Alan Modra <amodra@gmail.com> |
powerpc/modules: Fix alignment of .toc section in kernel modules powerpc64 gcc can generate code that offsets an address, to access part of an object in memory. If the address is a -mcmodel=medium toc pointer relative address then code like the following is possible. addis r9,r2,var@toc@ha ld r3,var@toc@l(r9) ld r4,(var+8)@toc@l(r9) This works fine so long as var is naturally aligned, *and* r2 is sufficiently aligned. If not, there is a possibility that the offset added to access var+8 wraps over a n*64k+32k boundary. Modules don't have any guarantee that r2 is sufficiently aligned. Moreover, code generated by older compilers generates a .toc section with 2**0 alignment, which can result in relocation failures at module load time even without the wrap problem. Thus, this patch links modules with an aligned .toc section (Makefile and module.lds changes), and forces alignment for out of tree modules or those without a .toc section (module_64.c changes). Signed-off-by: Alan Modra <amodra@gmail.com> [desnesn: updated patch to apply to powerpc-next kernel v4.15 ] Signed-off-by: Desnes A. Nunes do Rosario <desnesn@linux.vnet.ibm.com> [mpe: Fix out-of-tree build, swap -256 for ~0xff, reflow comment] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
#
1ea61ea2 |
|
14-Nov-2017 |
Josh Poimboeuf <jpoimboe@redhat.com> |
powerpc/modules: Improve restore_r2() error message Print the function address associated with the restore_r2() error to make it easier to debug the problem. Also clarify the wording a bit. Before: module_64: patch_foo: Expect noop after relocate, got 3c820000 After: module_64: patch_foo: Expected nop after call, got 7c630034 at netdev_has_upper_dev+0x54/0xb0 [patch_foo] Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> [mpe: Change noop to nop, as that's the name of the instruction] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
#
b9eab08d |
|
16-Nov-2017 |
Josh Poimboeuf <jpoimboe@redhat.com> |
powerpc/modules: Don't try to restore r2 after a sibling call When attempting to load a livepatch module, I got the following error: module_64: patch_module: Expect noop after relocate, got 3c820000 The error was triggered by the following code in unregister_netdevice_queue(): 14c: 00 00 00 48 b 14c <unregister_netdevice_queue+0x14c> 14c: R_PPC64_REL24 net_set_todo 150: 00 00 82 3c addis r4,r2,0 GCC didn't insert a nop after the branch to net_set_todo() because it's a sibling call, so it never returns. The nop isn't needed after the branch in that case. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Reviewed-and-tested-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
#
a443bf6e |
|
14-Nov-2017 |
Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> |
powerpc/modules: Add REL24 relocation support of livepatch symbols Livepatch re-uses module loader function apply_relocate_add() to write relocations, instead of managing them by arch-dependent klp_write_module_reloc() function. apply_relocate_add() doesn't understand livepatch symbols (marked with SHN_LIVEPATCH symbol section index) and assumes them to be local symbols by default for R_PPC64_REL24 relocation type. It fails with an error, when trying to calculate offset with local_entry_offset(): module_64: kpatch_meminfo: REL24 -1152921504897399800 out of range! Whereas livepatch symbols are essentially SHN_UNDEF, should be called via stub used for global calls. This issue can be fixed by teaching apply_relocate_add() to handle both SHN_UNDEF/SHN_LIVEPATCH symbols via the same stub. This patch extends SHN_UNDEF code to handle livepatch symbols too. Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
#
1c0437af |
|
10-Oct-2017 |
Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> |
powerpc/modules: Use WARN_ON() in stub_for_addr() Use WARN_ON(), while running out of stubs in stub_for_addr() and abort loading of the module instead of BUG_ON(). Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
#
71810db2 |
|
03-Feb-2017 |
Ard Biesheuvel <ardb@kernel.org> |
modversions: treat symbol CRCs as 32 bit quantities The modversion symbol CRCs are emitted as ELF symbols, which allows us to easily populate the kcrctab sections by relying on the linker to associate each kcrctab slot with the correct value. This has a couple of downsides: - Given that the CRCs are treated as memory addresses, we waste 4 bytes for each CRC on 64 bit architectures, - On architectures that support runtime relocation, a R_<arch>_RELATIVE relocation entry is emitted for each CRC value, which identifies it as a quantity that requires fixing up based on the actual runtime load offset of the kernel. This results in corrupted CRCs unless we explicitly undo the fixup (and this is currently being handled in the core module code) - Such runtime relocation entries take up 24 bytes of __init space each, resulting in a x8 overhead in [uncompressed] kernel size for CRCs. Switching to explicit 32 bit values on 64 bit architectures fixes most of these issues, given that 32 bit values are not treated as quantities that require fixing up based on the actual runtime load offset. Note that on some ELF64 architectures [such as PPC64], these 32-bit values are still emitted as [absolute] runtime relocatable quantities, even if the value resolves to a build time constant. Since relative relocations are always resolved at build time, this patch enables MODULE_REL_CRCS on powerpc when CONFIG_RELOCATABLE=y, which turns the absolute CRC references into relative references into .rodata where the actual CRC value is stored. So redefine all CRC fields and variables as u32, and redefine the __CRC_SYMBOL() macro for 64 bit builds to emit the CRC reference using inline assembler (which is necessary since 64-bit C code cannot use 32-bit types to hold memory addresses, even if they are ultimately resolved using values that do not exceed 0xffffffff). To avoid potential problems with legacy 32-bit architectures using legacy toolchains, the equivalent C definition of the kcrctab entry is retained for 32-bit architectures. Note that this mostly reverts commit d4703aefdbc8 ("module: handle ppc64 relocating kcrctabs when CONFIG_RELOCATABLE=y") Acked-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
9f751b82 |
|
25-Oct-2016 |
Michael Ellerman <mpe@ellerman.id.au> |
powerpc/module: Add support for R_PPC64_REL32 relocations We haven't seen these before, but the soon to be merged relative exception tables support causes them to be generated. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
#
31278b17 |
|
18-Jul-2016 |
Michael Ellerman <mpe@ellerman.id.au> |
powerpc/modules: Never restore r2 for a mprofile-kernel style mcount() call In the module loader we process relocations, and for long jumps we generate trampolines (aka stubs). At the call site for one of these trampolines we usually need to generate a load instruction to restore the TOC pointer into r2. There is one exception however, which is calls to mcount() using the mprofile-kernel ABI, they handle the TOC inside the stub, and so for them we do not generate a TOC load. The bug is in how the code in restore_r2() decides if it needs to generate the TOC load. It does so by looking for a nop following the branch, and if it sees a nop, it replaces it with the load. In general the compiler has no reason to generate a nop following the mcount() call and so that check works OK. However if we combine a jump label at the start of a function, with an early return, such that GCC applies the shrink-wrapping optimisation, we can then end up with an mcount call followed immediately by a nop. However the nop is not there for a TOC load, it is for the jump label. That confuses restore_r2() into replacing the jump label nop with a TOC load, which in turn confuses ftrace into replacing the mcount call with a b +8 (fixed in the previous commit). The end result is we jump over the jump label, which if it was supposed to return means we incorrectly run the body of the function. We have seen this in practice with some yet-to-be-merged patches that use jump labels more extensively. The fix is relatively simple, in restore_r2() we check for an mprofile-kernel style mcount() call first, before looking for the presence of a nop. Fixes: 153086644fd1 ("powerpc/ftrace: Add support for -mprofile-kernel ftrace ABI") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
#
f55d9665 |
|
06-Jun-2016 |
Michael Ellerman <mpe@ellerman.id.au> |
powerpc: Define and use PPC64_ELF_ABI_v2/v1 We're approaching 20 locations where we need to check for ELF ABI v2. That's fine, except the logic is a bit awkward, because we have to check that _CALL_ELF is defined and then what its value is. So check it once in asm/types.h and define PPC64_ELF_ABI_v2 when ELF ABI v2 is detected. We also have a few places where what we're really trying to check is that we are using the 64-bit v1 ABI, ie. function descriptors. So also add a #define for that, which simplifies several checks. Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
#
15308664 |
|
02-Mar-2016 |
Torsten Duwe <duwe@suse.de> |
powerpc/ftrace: Add support for -mprofile-kernel ftrace ABI The gcc switch -mprofile-kernel defines a new ABI for calling _mcount() very early in the function with minimal overhead. Although mprofile-kernel has been available since GCC 3.4, there were bugs which were only fixed recently. Currently it is known to work in GCC 4.9, 5 and 6. Additionally there are two possible code sequences generated by the flag, the first uses mflr/std/bl and the second is optimised to omit the std. Currently only gcc 6 has the optimised sequence. This patch supports both sequences. Initial work started by Vojtech Pavlik, used with permission. Key changes: - rework _mcount() to work for both the old and new ABIs. - implement new versions of ftrace_caller() and ftrace_graph_caller() which deal with the new ABI. - updates to __ftrace_make_nop() to recognise the new mcount calling sequence. - updates to __ftrace_make_call() to recognise the nop'ed sequence. - implement ftrace_modify_call(). - updates to the module loader to surpress the toc save in the module stub when calling mcount with the new ABI. Reviewed-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Torsten Duwe <duwe@suse.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
#
336a7b5d |
|
02-Mar-2016 |
Michael Ellerman <mpe@ellerman.id.au> |
powerpc/module: Create a special stub for ftrace_caller() In order to support the new -mprofile-kernel ABI, we need to be able to call from the module back to ftrace_caller() (in the kernel) without using the module's r2. That is because the function in this module which is calling ftrace_caller() may not have setup r2, if it doesn't otherwise need it (ie. it accesses no globals). To make that work we add a new stub which is used for calling ftrace_caller(), which uses the kernel toc instead of the module toc. Reviewed-by: Balbir Singh <bsingharora@gmail.com> Reviewed-by: Torsten Duwe <duwe@suse.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
#
f17c4e01 |
|
02-Mar-2016 |
Michael Ellerman <mpe@ellerman.id.au> |
powerpc/module: Mark module stubs with a magic value When a module is loaded, calls out to the kernel go via a stub which is generated at runtime. One of these stubs is used to call _mcount(), which is the default target of tracing calls generated by the compiler with -pg. If dynamic ftrace is enabled (which it typically is), another stub is used to call ftrace_caller(), which is the target of tracing calls when ftrace is actually active. ftrace then wants to disable the calls to _mcount() at module startup, and enable/disable the calls to ftrace_caller() when enabling/disabling tracing - all of these it does by patching the code. As part of that code patching, the ftrace code wants to confirm that the branch it is about to modify, is in fact a call to a module stub which calls _mcount() or ftrace_caller(). Currently it does that by inspecting the instructions and confirming they are what it expects. Although that works, the code to do it is pretty intricate because it requires lots of knowledge about the exact format of the stub. We can make that process easier by marking the generated stubs with a magic value, and then looking for that magic value. Altough this is not as rigorous as the current method, I believe it is sufficient in practice. Reviewed-by: Balbir Singh <bsingharora@gmail.com> Reviewed-by: Torsten Duwe <duwe@suse.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
#
136cd345 |
|
02-Mar-2016 |
Michael Ellerman <mpe@ellerman.id.au> |
powerpc/module: Only try to generate the ftrace_caller() stub once Currently we generate the module stub for ftrace_caller() at the bottom of apply_relocate_add(). However apply_relocate_add() is potentially called more than once per module, which means we will try to generate the ftrace_caller() stub multiple times. Although the current code deals with that correctly, ie. it only generates a stub the first time, it would be clearer to only try to generate the stub once. Note also on first reading it may appear that we generate a different stub for each section that requires relocation, but that is not the case. The code in stub_for_addr() that searches for an existing stub uses sechdrs[me->arch.stubs_section], ie. the single stub section for this module. A cleaner approach is to only generate the ftrace_caller() stub once, from module_finalize(). Although the original code didn't check to see if the stub was actually generated correctly, it seems prudent to add a check, so do that. And an additional benefit is we can clean the ifdefs up a little. Finally we must propagate the const'ness of some of the pointers passed to module_finalize(), but that is also an improvement. Reviewed-by: Balbir Singh <bsingharora@gmail.com> Reviewed-by: Torsten Duwe <duwe@suse.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
#
f15838e9 |
|
05-Feb-2016 |
Andreas Schwab <schwab@linux-m68k.org> |
powerpc: Fix dedotify for binutils >= 2.26 Since binutils 2.26 BFD is doing suffix merging on STRTAB sections. But dedotify modifies the symbol names in place, which can also modify unrelated symbols with a name that matches a suffix of a dotted name. To remove the leading dot of a symbol name we can just increment the pointer into the STRTAB section instead. Backport to all stables to avoid breakage when people update their binutils - mpe. Cc: stable@vger.kernel.org Signed-off-by: Andreas Schwab <schwab@linux-m68k.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
#
c153693d |
|
15-Jan-2016 |
Alan Modra <amodra@gmail.com> |
powerpc: Simplify module TOC handling PowerPC64 uses the symbol .TOC. much as other targets use _GLOBAL_OFFSET_TABLE_. It identifies the value of the GOT pointer (or in powerpc parlance, the TOC pointer). Global offset tables are generally local to an executable or shared library, or in the kernel, module. Thus it does not make sense for a module to resolve a relocation against .TOC. to the kernel's .TOC. value. A module has its own .TOC., and indeed the powerpc64 module relocation processing ignores the kernel value of .TOC. and instead calculates a module-local value. This patch removes code involved in exporting the kernel .TOC., tweaks modpost to ignore an undefined .TOC., and the module loader to twiddle the section symbol so that .TOC. isn't seen as undefined. Note that if the kernel was compiled with -msingle-pic-base then ELFv2 would not have function global entry code setting up r2. In that case the module call stubs would need to be modified to set up r2 using the kernel .TOC. value, requiring some of this code to be reinstated. mpe: Furthermore a change in binutils master (not yet released) causes the current way we handle the TOC to no longer work when building with MODVERSIONS=y and RELOCATABLE=n. The symptom is that modules can not be loaded due to there being no version found for TOC. Cc: stable@vger.kernel.org # 3.16+ Signed-off-by: Alan Modra <amodra@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
#
a61674bd |
|
12-Jan-2016 |
Ulrich Weigand <ulrich.weigand@de.ibm.com> |
powerpc/module: Handle R_PPC64_ENTRY relocations GCC 6 will include changes to generated code with -mcmodel=large, which is used to build kernel modules on powerpc64le. This was necessary because the large model is supposed to allow arbitrary sizes and locations of the code and data sections, but the ELFv2 global entry point prolog still made the unconditional assumption that the TOC associated with any particular function can be found within 2 GB of the function entry point: func: addis r2,r12,(.TOC.-func)@ha addi r2,r2,(.TOC.-func)@l .localentry func, .-func To remove this assumption, GCC will now generate instead this global entry point prolog sequence when using -mcmodel=large: .quad .TOC.-func func: .reloc ., R_PPC64_ENTRY ld r2, -8(r12) add r2, r2, r12 .localentry func, .-func The new .reloc triggers an optimization in the linker that will replace this new prolog with the original code (see above) if the linker determines that the distance between .TOC. and func is in range after all. Since this new relocation is now present in module object files, the kernel module loader is required to handle them too. This patch adds support for the new relocation and implements the same optimization done by the GNU linker. Cc: stable@vger.kernel.org Signed-off-by: Ulrich Weigand <ulrich.weigand@de.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
#
c7d1f6af |
|
16-Sep-2014 |
Anton Blanchard <anton@samba.org> |
powerpc: Use pr_fmt in module loader code Use pr_fmt to give some context to the error messages in the module code, and convert open coded debug printk to pr_debug. Use pr_err for error messages. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
#
c2cbcf53 |
|
24-Jun-2014 |
Laurent Dufour <ldufour@linux.vnet.ibm.com> |
powerpc/module: Fix TOC symbol CRC The commit 71ec7c55ed91 introduced the magic symbol ".TOC." for ELFv2 ABI. This symbol is built manually and has no CRC value computed. A zero value is put in the CRC section to avoid modpost complaining about a missing CRC. Unfortunately, this breaks the kernel module loading when the kernel is relocated (kdump case for instance) because of the relocation applied to the kcrctab values. This patch compute a CRC value for the TOC symbol which will match the one compute by the kernel when it is relocated - aka '0 - relocate_start' done in maybe_relocated called by check_version (module.c). Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com> Cc: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
|
#
872aa779 |
|
12-May-2014 |
Rusty Russell <rusty@rustcorp.com.au> |
powerpc/module: Fix stubs for BE A simple patch which was supposed to swap r12 and r11 also inexplicably changed the offset by two bytes. This instruction (to load r2) isn't used in LE, so it wasn't noticed. Fixes: b1ce369e82 ("powerpc: modules: use r12 for stub jump address.) Reported-by: Alistair Popple <alistair@popple.id.au> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Tested-by: Alistair Popple <alistair@popple.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
|
#
dd9fa162 |
|
03-Apr-2014 |
Anton Blanchard <anton@samba.org> |
powerpc/modules: Create module_trampoline_target() ftrace has way too much knowledge of our kernel module trampoline layout hidden inside it. Create module_trampoline_target() that gives the target address of a kernel module trampoline. Signed-off-by: Anton Blanchard <anton@samba.org>
|
#
83775b85 |
|
03-Apr-2014 |
Anton Blanchard <anton@samba.org> |
powerpc/modules: Create is_module_trampoline() ftrace has way too much knowledge of our kernel module trampoline layout hidden inside it. Create is_module_trampoline() that can abstract this away inside the module loader code. Signed-off-by: Anton Blanchard <anton@samba.org>
|
#
008d7a91 |
|
18-Mar-2014 |
Rusty Russell <rusty@rustcorp.com.au> |
powerpc: modules: implement stubs for ELFv2 ABI. ELFv2 doesn't use function descriptors, because it doesn't need to load a new r2 when calling into a function. On the other hand, you're supposed to use a local entry point for R_PPC_REL24 branches. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
|
#
5c729a11 |
|
18-Mar-2014 |
Rusty Russell <rusty@rustcorp.com.au> |
powerpc: modules: skip r2 setup for ELFv2 ELFv2 doesn't need to set up r2 when calling a function. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
|
#
b1ce369e |
|
18-Mar-2014 |
Rusty Russell <rusty@rustcorp.com.au> |
powerpc: modules: use r12 for stub jump address. In ELFv2, r12 is supposed to equal to PC on entry to a function. Our stubs use r11, so change swap that with r12. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
|
#
d2fae548 |
|
18-Mar-2014 |
Rusty Russell <rusty@rustcorp.com.au> |
powerpc: modules: change r2 save/restore offset for ELFv2 ABI. ELFv2 uses a different stack offset (24 vs 40) to save r2. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
|
#
5b12c5c6 |
|
18-Mar-2014 |
Rusty Russell <rusty@rustcorp.com.au> |
powerpc: modules: comment about de-dotifying symbols when using the ELFv2 ABI. ELFv2 doesn't use function descriptors, so we don't expect symbols to start with ".". But because depmod and modpost strip ".", and we have the special symbol ".TOC.", we still need to do it. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
|
#
0906584a |
|
18-Mar-2014 |
Rusty Russell <rusty@rustcorp.com.au> |
powerpc: Handle new ELFv2 module relocations The new ELF ABI tends to use R_PPC64_REL16_LO and R_PPC64_REL16_HA relocations (PC-relative), so implement them. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
|
#
4edebbea |
|
18-Mar-2014 |
Rusty Russell <rusty@rustcorp.com.au> |
powerpc: Fix up TOC. for modules. The kernel resolved the '.TOC.' to a fake symbol, so we need to fix it up to point to our .toc section plus 0x8000. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
|
#
d247da0a |
|
18-Mar-2014 |
Rusty Russell <rusty@rustcorp.com.au> |
powerpc: modules implement R_PPC64_TOCSAVE relocation. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
|
#
0e60e46e |
|
18-Mar-2014 |
Rusty Russell <rusty@rustcorp.com.au> |
powerpc: make module stub code endian independent By representing them as words, rather than chars, we can avoid endian ifdefs. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
|
#
b88c4767 |
|
28-Oct-2013 |
Robert Jennings <rcj@linux.vnet.ibm.com> |
powerpc: Move local setup.h declarations to arch includes Move the few declarations from arch/powerpc/kernel/setup.h into arch/powerpc/include/asm/setup.h. This resolves a sparse warning for arch/powerpc/mm/numa.c which defines do_init_bootmem() but can't include the setup.h header in the prior path. Resolves: arch/powerpc/mm/numa.c:998:13: warning: symbol 'do_init_bootmem' was not declared. Should it be static? Signed-off-by: Robert C Jennings <rcj@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
|
#
fed8393e |
|
20-Sep-2013 |
Eugene Surovegin <ebs@ebshome.net> |
powerpc: Make kernel module helper endian-safe. Signed-off-by: Eugene Surovegin <surovegin@google.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
|
#
1fbe9cf2 |
|
26-Nov-2012 |
Anton Blanchard <anton@samba.org> |
powerpc: Build kernel with -mcmodel=medium Finally remove the two level TOC and build with -mcmodel=medium. Unfortunately we can't build modules with -mcmodel=medium due to the tricks the kernel module loader plays with percpu data: # -mcmodel=medium breaks modules because it uses 32bit offsets from # the TOC pointer to create pointers where possible. Pointers into the # percpu data area are created by this method. # # The kernel module loader relocates the percpu data section from the # original location (starting with 0xd...) to somewhere in the base # kernel percpu data space (starting with 0xc...). We need a full # 64bit relocation for this to work, hence -mcmodel=large. On older kernels we fall back to the two level TOC (-mminimal-toc) Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
|
#
66574cc0 |
|
30-Jun-2011 |
Jonas Bonn <jonas@southpole.se> |
modules: make arch's use default loader hooks This patch removes all the module loader hook implementations in the architecture specific code where the functionality is the same as that now provided by the recently added default hooks. Signed-off-by: Jonas Bonn <jonas@southpole.se> Acked-by: Mike Frysinger <vapier@gentoo.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Tested-by: Michal Simek <monstr@monstr.eu> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
|
#
16c57b36 |
|
10-Feb-2009 |
Kumar Gala <galak@kernel.crashing.org> |
powerpc: Unify opcode definitions and support Create a new header that becomes a single location for defining PowerPC opcodes used by code that is either generationg instructions at runtime (fixups, debug, etc.), emulating instructions, or just compiling instructions old assemblers don't know about. We currently don't handle the floating point emulation or alignment decode as both are better handled by the specific decode support they already have. Added support for the new dcbzl, dcbal, msgsnd, tlbilx, & wait instructions since older assemblers don't know about them. Signed-off-by: Kumar Gala <galak@kernel.crashing.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
|
#
f48cb8b4 |
|
14-Nov-2008 |
Steven Rostedt <srostedt@redhat.com> |
powerpc/ppc64: ftrace, handle module trampolines for dyn ftrace Impact: Allow 64 bit PowerPC to trace modules with dynamic ftrace This adds code to handle the PPC64 module trampolines, and allows for PPC64 to use dynamic ftrace. Thanks to Paul Mackerras for these updates: - fix the mod and rec->arch.mod NULL checks. - fix to is_bl_op compare. Thanks to Milton Miller for: - finding the nasty race with using two nops, and recommending instead that I use a branch 8 forward. Signed-off-by: Steven Rostedt <srostedt@redhat.com>
|
#
2d291e90 |
|
09-Sep-2008 |
James Bottomley <James.Bottomley@HansenPartnership.com> |
Fix compile failure with non modular builds Commit deac93df26b20cf8438339b5935b5f5643bc30c9 ("lib: Correct printk %pF to work on all architectures") broke the non modular builds by moving an essential function into modules.c. Fix this by moving it out again and into asm/sections.h as an inline. To do this, the definition of struct ppc64_opd_entry has been lifted out of modules.c and put in asm/elf.h where it belongs. Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
|
#
deac93df |
|
03-Sep-2008 |
James Bottomley <James.Bottomley@HansenPartnership.com> |
lib: Correct printk %pF to work on all architectures It was introduced by "vsprintf: add support for '%pS' and '%pF' pointer formats" in commit 0fe1ef24f7bd0020f29ffe287dfdb9ead33ca0b2. However, the current way its coded doesn't work on parisc64. For two reasons: 1) parisc isn't in the #ifdef and 2) parisc has a different format for function descriptors Make dereference_function_descriptor() more accommodating by allowing architecture overrides. I put the three overrides (for parisc64, ppc64 and ia64) in arch/kernel/module.c because that's where the kernel internal linker which knows how to deal with function descriptors sits. Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Tony Luck <tony.luck@intel.com> Acked-by: Kyle McMartin <kyle@mcmartin.ca> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
#
b7bcda63 |
|
23-Jun-2008 |
Michael Ellerman <michael@ellerman.id.au> |
powerpc: Add PPC_NOP_INSTR, a hash define for the preferred nop instruction A bunch of code has hard-coded the value for a "nop" instruction, it would be nice to have a #define for it. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Acked-by: Kumar Gala <galak@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
|
#
f0c426bc |
|
20-Jun-2008 |
Kumar Gala <galak@kernel.crashing.org> |
powerpc: Move common module code into its own file Refactor common code between ppc32 and ppc64 module handling into a shared filed. Signed-off-by: Kumar Gala <galak@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
|
#
eda09fbd |
|
13-Nov-2007 |
Emil Medve <Emilian.Medve@Freescale.com> |
[POWERPC] Optimize counting distinct entries in the relocation sections When a module has relocation sections with tens of thousands of entries, counting the distinct/unique entries only (i.e. no duplicates) at load time can take tens of seconds and up to minutes. The sore point is the count_relocs() function which is called as part of the architecture specific module loading processing path: -> load_module() generic -> module_frob_arch_sections() arch specific -> get_plt_size() 32-bit -> get_stubs_size() 64-bit -> count_relocs() Here count_relocs is being called to find out how many distinct targets of R_PPC_REL24 relocations there are, since each distinct target needs a PLT entry or a stub created for it. The previous counting algorithm has O(n^2) complexity. Basically two solutions were proposed on the e-mail list: a hash based approach and a sort based approach. The hash based approach is the fastest (O(n)) but the has it needs additional memory and for certain corner cases it could take lots of memory due to the degeneration of the hash. One such proposal was submitted here: http://ozlabs.org/pipermail/linuxppc-dev/2007-June/037641.html The sort based approach is slower (O(n * log n + n)) but if the sorting is done "in place" it doesn't need additional memory. This has O(n + n * log n) complexity with no additional memory requirements. This commit implements the in-place sort option. Signed-off-by: Emil Medve <Emilian.Medve@Freescale.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
|
#
73c9ceab |
|
08-Dec-2006 |
Jeremy Fitzhardinge <jeremy@goop.org> |
[POWERPC] Generic BUG for powerpc This makes powerpc use the generic BUG machinery. The biggest reports the function name, since it is redundant with kallsyms, and not needed in general. There is an overall reduction of code, since module_32/64 duplicated several functions. Unfortunately there's no way to tell gcc that BUG won't return, so the BUG macro includes a goto loop. This will generate a real jmp instruction, which is never used. [akpm@osdl.org: build fix] [paulus@samba.org: remove infinite loop in BUG_ON] Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Andi Kleen <ak@muc.de> Cc: Hugh Dickens <hugh@veritas.com> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
|
#
21c4ff80 |
|
19-Oct-2006 |
Benjamin Herrenschmidt <benh@kernel.crashing.org> |
[POWERPC] Support feature fixups in modules This patch adds support for feature fixups in modules. This involves adding support for R_PPC64_REL64 relocs to the 64 bits module loader. It also modifies modpost.c to ignore the powerpc fixup sections (or it would warn when used in .init.text). Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Olof Johansson <olof@lixom.net> Signed-off-by: Paul Mackerras <paulus@samba.org>
|
#
f749edae |
|
24-Apr-2006 |
Alan Modra <amodra@bigpond.net.au> |
[PATCH] powerpc64: Fix loading of modules without a .toc section Normally, ppc64 module .ko files contain a table-of-contents (.toc) section, but if the module doesn't reference any static or external data or external procedures, it is possible for gcc/binutils to generate a .ko that doesn't have a .toc. Currently the module loader refuses to load such a module, since it needs the address of the .toc section to use in relocations. This patch fixes the problem by using the address of the .stubs section instead, which is an acceptable substitute in this situation. Signed-off-by: Paul Mackerras <paulus@samba.org>
|
#
7568cb4e |
|
13-Nov-2005 |
Paul Mackerras <paulus@samba.org> |
powerpc: Move most remaining ppc64 files over to arch/powerpc Also deletes files in arch/ppc64 that are no longer used now that we don't compile with ARCH=ppc64 any more. Signed-off-by: Paul Mackerras <paulus@samba.org>
|