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* powerpc/64s: Fix crashes when toggling entry flush barrierMichael Ellerman2021-05-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit aec86b052df6541cc97c5fca44e5934cbea4963b upstream. The entry flush mitigation can be enabled/disabled at runtime via a debugfs file (entry_flush), which causes the kernel to patch itself to enable/disable the relevant mitigations. However depending on which mitigation we're using, it may not be safe to do that patching while other CPUs are active. For example the following crash: sleeper[15639]: segfault (11) at c000000000004c20 nip c000000000004c20 lr c000000000004c20 Shows that we returned to userspace with a corrupted LR that points into the kernel, due to executing the partially patched call to the fallback entry flush (ie. we missed the LR restore). Fix it by doing the patching under stop machine. The CPUs that aren't doing the patching will be spinning in the core of the stop machine logic. That is currently sufficient for our purposes, because none of the patching we do is to that code or anywhere in the vicinity. Fixes: f79643787e0a ("powerpc/64s: flush L1D on kernel entry") Cc: stable@vger.kernel.org # v5.10+ Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210506044959.1298123-2-mpe@ellerman.id.au Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc: Stop exporting __clear_user which is now inlined.Michal Suchanek2020-12-11
| | | | | | | | | | | Stable commit 452e2a83ea23 ("powerpc: Fix __clear_user() with KUAP enabled") redefines __clear_user as inline function but does not remove the export. Fixes: 452e2a83ea23 ("powerpc: Fix __clear_user() with KUAP enabled") Signed-off-by: Michal Suchanek <msuchanek@suse.de> Acked-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/64s: flush L1D after user accessesNicholas Piggin2020-11-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | commit 9a32a7e78bd0cd9a9b6332cbdc345ee5ffd0c5de upstream. IBM Power9 processors can speculatively operate on data in the L1 cache before it has been completely validated, via a way-prediction mechanism. It is not possible for an attacker to determine the contents of impermissible memory using this method, since these systems implement a combination of hardware and software security measures to prevent scenarios where protected data could be leaked. However these measures don't address the scenario where an attacker induces the operating system to speculatively execute instructions using data that the attacker controls. This can be used for example to speculatively bypass "kernel user access prevention" techniques, as discovered by Anthony Steinhauser of Google's Safeside Project. This is not an attack by itself, but there is a possibility it could be used in conjunction with side-channels or other weaknesses in the privileged code to construct an attack. This issue can be mitigated by flushing the L1 cache between privilege boundaries of concern. This patch flushes the L1 cache after user accesses. This is part of the fix for CVE-2020-4788. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc: Fix __clear_user() with KUAP enabledAndrew Donnellan2020-11-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | commit 61e3acd8c693a14fc69b824cb5b08d02cb90a6e7 upstream. The KUAP implementation adds calls in clear_user() to enable and disable access to userspace memory. However, it doesn't add these to __clear_user(), which is used in the ptrace regset code. As there's only one direct user of __clear_user() (the regset code), and the time taken to set the AMR for KUAP purposes is going to dominate the cost of a quick access_ok(), there's not much point having a separate path. Rename __clear_user() to __arch_clear_user(), and make __clear_user() just call clear_user(). Reported-by: syzbot+f25ecf4b2982d8c7a640@syzkaller-ppc64.appspotmail.com Reported-by: Daniel Axtens <dja@axtens.net> Suggested-by: Michael Ellerman <mpe@ellerman.id.au> Fixes: de78a9c42a79 ("powerpc: Add a framework for Kernel Userspace Access Protection") Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com> [mpe: Use __arch_clear_user() for the asm version like arm64 & nds32] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20191209132221.15328-1-ajd@linux.ibm.com Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc: Add a framework for user access trackingChristophe Leroy2020-11-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Backported from commit de78a9c42a79 ("powerpc: Add a framework for Kernel Userspace Access Protection"). Here we don't try to add the KUAP framework, we just want the helper functions because we want to put uaccess flush helpers in them. In terms of fixes, we don't need commit 1d8f739b07bd ("powerpc/kuap: Fix set direction in allow/prevent_user_access()") as we don't have real KUAP. Likewise as all our allows are noops and all our prevents are just flushes, we don't need commit 9dc086f1e9ef ("powerpc/futex: Fix incorrect user access blocking") The other 2 fixes we do need. The original description is: This patch implements a framework for Kernel Userspace Access Protection. Then subarches will have the possibility to provide their own implementation by providing setup_kuap() and allow/prevent_user_access(). Some platforms will need to know the area accessed and whether it is accessed from read, write or both. Therefore source, destination and size and handed over to the two functions. mpe: Rename to allow/prevent rather than unlock/lock, and add read/write wrappers. Drop the 32-bit code for now until we have an implementation for it. Add kuap to pt_regs for 64-bit as well as 32-bit. Don't split strings, use pr_crit_ratelimited(). Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Russell Currey <ruscur@russell.cc> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc/64s: flush L1D on kernel entryNicholas Piggin2020-11-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | commit f79643787e0a0762d2409b7b8334e83f22d85695 upstream. IBM Power9 processors can speculatively operate on data in the L1 cache before it has been completely validated, via a way-prediction mechanism. It is not possible for an attacker to determine the contents of impermissible memory using this method, since these systems implement a combination of hardware and software security measures to prevent scenarios where protected data could be leaked. However these measures don't address the scenario where an attacker induces the operating system to speculatively execute instructions using data that the attacker controls. This can be used for example to speculatively bypass "kernel user access prevention" techniques, as discovered by Anthony Steinhauser of Google's Safeside Project. This is not an attack by itself, but there is a possibility it could be used in conjunction with side-channels or other weaknesses in the privileged code to construct an attack. This issue can be mitigated by flushing the L1 cache between privilege boundaries of concern. This patch flushes the L1 cache on kernel entry. This is part of the fix for CVE-2020-4788. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc/lib: fix book3s/32 boot failure due to code patchingChristophe Leroy2019-05-16
| | | | | | | | | | | | | | | | | | | | | | | | commit b45ba4a51cde29b2939365ef0c07ad34c8321789 upstream. Commit 51c3c62b58b3 ("powerpc: Avoid code patching freed init sections") accesses 'init_mem_is_free' flag too early, before the kernel is relocated. This provokes early boot failure (before the console is active). As it is not necessary to do this verification that early, this patch moves the test into patch_instruction() instead of __patch_instruction(). This modification also has the advantage of avoiding unnecessary remappings. Fixes: 51c3c62b58b3 ("powerpc: Avoid code patching freed init sections") Cc: stable@vger.kernel.org # 4.13+ Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc/fsl: Add infrastructure to fixup branch predictor flushDiana Craciun2019-05-16
| | | | | | | | | | | | | | | | commit 76a5eaa38b15dda92cd6964248c39b5a6f3a4e9d upstream. In order to protect against speculation attacks (Spectre variant 2) on NXP PowerPC platforms, the branch predictor should be flushed when the privillege level is changed. This patch is adding the infrastructure to fixup at runtime the code sections that are performing the branch predictor flush depending on a boot arg parameter which is added later in a separate patch. Signed-off-by: Diana Craciun <diana.craciun@nxp.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc: Avoid code patching freed init sectionsMichael Neuling2019-05-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 51c3c62b58b357e8d35e4cc32f7b4ec907426fe3 upstream. This stops us from doing code patching in init sections after they've been freed. In this chain: kvm_guest_init() -> kvm_use_magic_page() -> fault_in_pages_readable() -> __get_user() -> __get_user_nocheck() -> barrier_nospec(); We have a code patching location at barrier_nospec() and kvm_guest_init() is an init function. This whole chain gets inlined, so when we free the init section (hence kvm_guest_init()), this code goes away and hence should no longer be patched. We seen this as userspace memory corruption when using a memory checker while doing partition migration testing on powervm (this starts the code patching post migration via /sys/kernel/mobility/migration). In theory, it could also happen when using /sys/kernel/debug/powerpc/barrier_nospec. Signed-off-by: Michael Neuling <mikey@neuling.org> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc/asm: Add a patch_site macro & helpers for patching instructionsMichael Ellerman2019-05-16
| | | | | | | | | | | | | | | | | | | | | | commit 06d0bbc6d0f56dacac3a79900e9a9a0d5972d818 upstream. Add a macro and some helper C functions for patching single asm instructions. The gas macro means we can do something like: 1: nop patch_site 1b, patch__foo Which is less visually distracting than defining a GLOBAL symbol at 1, and also doesn't pollute the symbol table which can confuse eg. perf. These are obviously similar to our existing feature sections, but are not automatically patched based on CPU/MMU features, rather they are designed to be manually patched by C code at some arbitrary point. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc/fsl: Add barrier_nospec implementation for NXP PowerPC Book3EDiana Craciun2019-05-16
| | | | | | | | | | | | commit ebcd1bfc33c7a90df941df68a6e5d4018c022fba upstream. Implement the barrier_nospec as a isync;sync instruction sequence. The implementation uses the infrastructure built for BOOK3S 64. Signed-off-by: Diana Craciun <diana.craciun@nxp.com> [mpe: Add PPC_INST_ISYNC for backport] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc/64: Add CONFIG_PPC_BARRIER_NOSPECMichael Ellerman2019-05-16
| | | | | | | | | | | | commit 179ab1cbf883575c3a585bcfc0f2160f1d22a149 upstream. Add a config symbol to encode which platforms support the barrier_nospec speculation barrier. Currently this is just Book3S 64 but we will add Book3E in a future patch. Signed-off-by: Diana Craciun <diana.craciun@nxp.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc/64s: Patch barrier_nospec in modulesMichal Suchanek2019-05-16
| | | | | | | | | | | | | | | | commit 815069ca57c142eb71d27439bc27f41a433a67b3 upstream. Note that unlike RFI which is patched only in kernel the nospec state reflects settings at the time the module was loaded. Iterating all modules and re-patching every time the settings change is not implemented. Based on lwsync patching. Signed-off-by: Michal Suchanek <msuchanek@suse.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc/64s: Add support for ori barrier_nospec patchingMichal Suchanek2019-05-16
| | | | | | | | | | | | | | | | commit 2eea7f067f495e33b8b116b35b5988ab2b8aec55 upstream. Based on the RFI patching. This is required to be able to disable the speculation barrier. Only one barrier type is supported and it does nothing when the firmware does not enable it. Also re-patching modules is not supported So the only meaningful thing that can be done is patching out the speculation barrier at boot when the user says it is not wanted. Signed-off-by: Michal Suchanek <msuchanek@suse.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc/64s: Add support for a store forwarding barrier at kernel entry/exitNicholas Piggin2019-05-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit a048a07d7f4535baa4cbad6bc024f175317ab938 upstream. On some CPUs we can prevent a vulnerability related to store-to-load forwarding by preventing store forwarding between privilege domains, by inserting a barrier in kernel entry and exit paths. This is known to be the case on at least Power7, Power8 and Power9 powerpc CPUs. Barriers must be inserted generally before the first load after moving to a higher privilege, and after the last store before moving to a lower privilege, HV and PR privilege transitions must be protected. Barriers are added as patch sections, with all kernel/hypervisor entry points patched, and the exit points to lower privilge levels patched similarly to the RFI flush patching. Firmware advertisement is not implemented yet, so CPU flush types are hard coded. Thanks to Michal Suchánek for bug fixes and review. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com> Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michal Suchánek <msuchanek@suse.de> [mpe: 4.4 doesn't have EXC_REAL_OOL_MASKABLE, so do it manually] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc/rfi-flush: Differentiate enabled and patched flush typesMauricio Faria de Oliveira2019-05-16
| | | | | | | | | | | | | | | | | | | | | commit 0063d61ccfc011f379a31acaeba6de7c926fed2c upstream. Currently the rfi-flush messages print 'Using <type> flush' for all enabled_flush_types, but that is not necessarily true -- as now the fallback flush is always enabled on pseries, but the fixup function overwrites its nop/branch slot with other flush types, if available. So, replace the 'Using <type> flush' messages with '<type> flush is available'. Also, print the patched flush types in the fixup function, so users can know what is (not) being used (e.g., the slower, fallback flush, or no flush type at all if flush is disabled via the debugfs switch). Suggested-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc/lib: Fix off-by-one in alternate feature patchingMichael Ellerman2018-04-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit b8858581febb050688e276b956796bc4a78299ed upstream. When we patch an alternate feature section, we have to adjust any relative branches that branch out of the alternate section. But currently we have a bug if we have a branch that points to past the last instruction of the alternate section, eg: FTR_SECTION_ELSE 1: b 2f or 6,6,6 2: ALT_FTR_SECTION_END(...) nop This will result in a relative branch at 1 with a target that equals the end of the alternate section. That branch does not need adjusting when it's moved to the non-else location. Currently we do adjust it, resulting in a branch that goes off into the link-time location of the else section, which is junk. The fix is to not patch branches that have a target == end of the alternate section. Fixes: d20fe50a7b3c ("KVM: PPC: Book3S HV: Branch inside feature section") Fixes: 9b1a735de64c ("powerpc: Add logic to patch alternative feature sections") Cc: stable@vger.kernel.org # v2.6.27+ Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc/64s: Add support for RFI flush of L1-D cacheMichael Ellerman2018-02-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit aa8a5e0062ac940f7659394f4817c948dc8c0667 upstream. On some CPUs we can prevent the Meltdown vulnerability by flushing the L1-D cache on exit from kernel to user mode, and from hypervisor to guest. This is known to be the case on at least Power7, Power8 and Power9. At this time we do not know the status of the vulnerability on other CPUs such as the 970 (Apple G5), pasemi CPUs (AmigaOne X1000) or Freescale CPUs. As more information comes to light we can enable this, or other mechanisms on those CPUs. The vulnerability occurs when the load of an architecturally inaccessible memory region (eg. userspace load of kernel memory) is speculatively executed to the point where its result can influence the address of a subsequent speculatively executed load. In order for that to happen, the first load must hit in the L1, because before the load is sent to the L2 the permission check is performed. Therefore if no kernel addresses hit in the L1 the vulnerability can not occur. We can ensure that is the case by flushing the L1 whenever we return to userspace. Similarly for hypervisor vs guest. In order to flush the L1-D cache on exit, we add a section of nops at each (h)rfi location that returns to a lower privileged context, and patch that with some sequence. Newer firmwares are able to advertise to us that there is a special nop instruction that flushes the L1-D. If we do not see that advertised, we fall back to doing a displacement flush in software. For guest kernels we support migration between some CPU versions, and different CPUs may use different flush instructions. So that we are prepared to migrate to a machine with a different flush instruction activated, we may have to patch more than one flush instruction at boot if the hypervisor tells us to. In the end this patch is mostly the work of Nicholas Piggin and Michael Ellerman. However a cast of thousands contributed to analysis of the issue, earlier versions of the patch, back ports testing etc. Many thanks to all of them. Tested-by: Jon Masters <jcm@redhat.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> [Balbir - back ported to stable with changes] Signed-off-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc: Fix emulation of mfocrf in emulate_step()Anton Blanchard2017-07-27
| | | | | | | | | | | | | | | | | | commit 64e756c55aa46fc18fd53e8f3598b73b528d8637 upstream. From POWER4 onwards, mfocrf() only places the specified CR field into the destination GPR, and the rest of it is set to 0. The PowerPC AS from version 3.0 now requires this behaviour. The emulation code currently puts the entire CR into the destination GPR. Fix it. Fixes: 6888199f7fe5 ("[POWERPC] Emulate more instructions in software") Signed-off-by: Anton Blanchard <anton@samba.org> Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc: Fix emulation of mcrf in emulate_step()Anton Blanchard2017-07-27
| | | | | | | | | | | | | | | | commit 87c4b83e0fe234a1f0eed131ab6fa232036860d5 upstream. The mcrf emulation code was using the CR field number directly as the shift value, without taking into account that CR fields are numbered from 0-7 starting at the high bits. That meant it was looking at the CR fields in the reverse order. Fixes: cf87c3f6b647 ("powerpc: Emulate icbi, mcrf and conditional-trap instructions") Signed-off-by: Anton Blanchard <anton@samba.org> Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc: Emulation support for load/store instructions on LERavi Bangoria2017-03-18
| | | | | | | | | | | | | | commit e148bd17f48bd17fca2f4f089ec879fa6e47e34c upstream. emulate_step() uses a number of underlying kernel functions that were initially not enabled for LE. This has been rectified since. So, fix emulate_step() for LE for the corresponding instructions. Reported-by: Anton Blanchard <anton@samba.org> Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc/64: Fix incorrect return value from __copy_tofrom_userPaul Mackerras2016-10-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 1a34439e5a0b2235e43f96816dbb15ee1154f656 upstream. Debugging a data corruption issue with virtio-net/vhost-net led to the observation that __copy_tofrom_user was occasionally returning a value 16 larger than it should. Since the return value from __copy_tofrom_user is the number of bytes not copied, this means that __copy_tofrom_user can occasionally return a value larger than the number of bytes it was asked to copy. In turn this can cause higher-level copy functions such as copy_page_to_iter_iovec to corrupt memory by copying data into the wrong memory locations. It turns out that the failing case involves a fault on the store at label 79, and at that point the first unmodified byte of the destination is at R3 + 16. Consequently the exception handler for that store needs to add 16 to R3 before using it to work out how many bytes were not copied, but in this one case it was not adding the offset to R3. To fix it, this moves the label 179 to the point where we add 16 to R3. I have checked manually all the exception handlers for the loads and stores in this code and the rest of them are correct (it would be excellent to have an automated test of all the exception cases). This bug has been present since this code was initially committed in May 2002 to Linux version 2.5.20. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc32: memset: only use dcbz once cache is enabledLEROY Christophe2015-09-17
| | | | | | | | | | | | | | | | | | memset() uses instruction dcbz to speed up clearing by not wasting time loading cache line with data that will be overwritten. Some platform like mpc52xx do no have cache active at startup and can therefore not use memset(). Allthough no part of the code explicitly uses memset(), GCC may make calls to it. This patch modifies memset() such that at startup, memset() unconditionally skip the optimised bloc that uses dcbz instruction. Once the initial MMU is set up, in machine_init() we patch memset() by replacing this inconditional jump by a NOP Tested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc32: memcpy: only use dcbz once cache is enabledLEROY Christophe2015-09-17
| | | | | | | | | | | | | | | | | | | | memcpy() uses instruction dcbz to speed up copy by not wasting time loading cache line with data that will be overwritten. Some platform like mpc52xx do no have cache active at startup and can therefore not use memcpy(). Allthough no part of the code explicitly uses memcpy(), GCC makes calls to it. This patch modifies memcpy() such that at startup, memcpy() unconditionally jumps to generic_memcpy() which doesn't use the dcbz instruction. Once the initial MMU is set up, in machine_init() we patch memcpy() by replacing this inconditional jump by a NOP Reported-by: Michal Sojka <sojkam1@fel.cvut.cz> Tested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/32: Few optimisations in memcpyLEROY Christophe2015-08-07
| | | | | | | | | This patch adds a few optimisations in memcpy functions by using lbzu/stbu instead of lxb/stb and by re-ordering insn inside a loop to reduce latency due to loading Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <scottwood@freescale.com>
* powerpc/32: cacheable_memcpy becomes memcpyLEROY Christophe2015-08-07
| | | | | | | | | | | | | | | cacheable_memcpy uses dcbz instruction and is more efficient than memcpy when the destination is in RAM. If the destination is in an io area, memcpy_toio() is normally used, not memcpy This patch renames memcpy as generic_memcpy, and renames cacheable_memcpy as memcpy On MPC885, we get approximatly 7% increase of the transfer rate on an FTP reception Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <scottwood@freescale.com>
* powerpc/32: Merge the new memset() with the old oneLEROY Christophe2015-08-07
| | | | | | | | cacheable_memzero() which has become the new memset() and the old memset() are quite similar, so just merge them. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <scottwood@freescale.com>
* powerpc/32: memset(0): use cacheable_memzeroLEROY Christophe2015-08-07
| | | | | | | | | | | | | | cacheable_memzero uses dcbz instruction and is more efficient than memset(0) when the destination is in RAM This patch renames memset as generic_memset, and defines memset as a prolog to cacheable_memzero. This prolog checks if the byte to set is 0. If not, it falls back to generic_memcpy() cacheable_memzero disappears as it is not referenced anywhere anymore Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <scottwood@freescale.com>
* Partially revert "powerpc: Remove duplicate cacheable_memcpy/memzero functions"LEROY Christophe2015-08-07
| | | | | | | | | | | | | This partially reverts commit 'powerpc: Remove duplicate cacheable_memcpy/memzero functions ("b05ae4ee602b7dc90771408ccf0972e1b3801a35")' Functions cacheable_memcpy/memzero are more efficient than memcpy/memset as they use the dcbz instruction which avoids refill of the cacheline with the data that we will overwrite. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <scottwood@freescale.com>
* powerpc: put csum_tcpudp_magic inlineLEROY Christophe2015-08-07
| | | | | | | | | | | | | csum_tcpudp_magic() is only a few instructions, and does modify really few registers. So it is not worth having it as a separate function and suffer function branching and saving of volatile registers. This patch makes it inline by use of the already existing csum_tcpudp_nofold() function. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <scottwood@freescale.com>
* Merge tag 'powerpc-4.2-1' of ↵Linus Torvalds2015-06-24
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux Pull powerpc updates from Michael Ellerman: - disable the 32-bit vdso when building LE, so we can build with a 64-bit only toolchain. - EEH fixes from Gavin & Richard. - enable the sys_kcmp syscall from Laurent. - sysfs control for fastsleep workaround from Shreyas. - expose OPAL events as an irq chip by Alistair. - MSI ops moved to pci_controller_ops by Daniel. - fix for kernel to userspace backtraces for perf from Anton. - merge pseries and pseries_le defconfigs from Cyril. - CXL in-kernel API from Mikey. - OPAL prd driver from Jeremy. - fix for DSCR handling & tests from Anshuman. - Powernv flash mtd driver from Cyril. - dynamic DMA Window support on powernv from Alexey. - LLVM clang fixes & workarounds from Anton. - reworked version of the patch to abort syscalls when transactional. - fix the swap encoding to support 4TB, from Aneesh. - various fixes as usual. - Freescale updates from Scott: Highlights include more 8xx optimizations, an e6500 hugetlb optimization, QMan device tree nodes, t1024/t1023 support, and various fixes and cleanup. * tag 'powerpc-4.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: (180 commits) cxl: Fix typo in debug print cxl: Add CXL_KERNEL_API config option powerpc/powernv: Fix wrong IOMMU table in pnv_ioda_setup_bus_dma() powerpc/mm: Change the swap encoding in pte. powerpc/mm: PTE_RPN_MAX is not used, remove the same powerpc/tm: Abort syscalls in active transactions powerpc/iommu/ioda2: Enable compile with IOV=on and IOMMU_API=off powerpc/include: Add opal-prd to installed uapi headers powerpc/powernv: fix construction of opal PRD messages powerpc/powernv: Increase opal-irqchip initcall priority powerpc: Make doorbell check preemption safe powerpc/powernv: pnv_init_idle_states() should only run on powernv macintosh/nvram: Remove as unused powerpc: Don't use gcc specific options on clang powerpc: Don't use -mno-strict-align on clang powerpc: Only use -mtraceback=no, -mno-string and -msoft-float if toolchain supports it powerpc: Only use -mabi=altivec if toolchain supports it powerpc: Fix duplicate const clang warning in user access code vfio: powerpc/spapr: Support Dynamic DMA windows vfio: powerpc/spapr: Register memory and define IOMMU v2 ...
| * powerpc: Only use -mabi=altivec if toolchain supports itAnton Blanchard2015-06-11
| | | | | | | | | | | | | | | | The -mabi=altivec option is not recognised on LLVM, so use call cc-option to check for support. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | sched/preempt, powerpc: Disable preemption in enable_kernel_altivec() explicitlyDavid Hildenbrand2015-05-19
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | enable_kernel_altivec() has to be called with disabled preemption. Let's make this explicit, to prepare for pagefault_disable() not touching preemption anymore. Reviewed-and-tested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: David.Laight@ACULAB.COM Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: airlied@linux.ie Cc: akpm@linux-foundation.org Cc: bigeasy@linutronix.de Cc: borntraeger@de.ibm.com Cc: daniel.vetter@intel.com Cc: heiko.carstens@de.ibm.com Cc: herbert@gondor.apana.org.au Cc: hocko@suse.cz Cc: hughd@google.com Cc: mst@redhat.com Cc: paulus@samba.org Cc: ralf@linux-mips.org Cc: schwidefsky@de.ibm.com Cc: yang.shi@windriver.com Link: http://lkml.kernel.org/r/1431359540-32227-14-git-send-email-dahi@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* powerpc: Replace mem_init_done with slab_is_available()Michael Ellerman2015-04-10
| | | | | | | | | | | | | We have a powerpc specific global called mem_init_done which is "set on boot once kmalloc can be called". But that's not *quite* true. We set it at the bottom of mem_init(), and rely on the fact that mm_init() calls kmem_cache_init() immediately after that, and nothing is running in parallel. So replace it with the generic and 100% correct slab_is_available(). Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* Merge branch 'next-misc' of ↵Michael Ellerman2015-03-26
|\ | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc into test Merge miscellaneous bits from benh. Fix a minor conflict with OpalMessageType changing names to opal_msg_type.
| * cpufreq/ppc: Add missing #include <asm/smp.h>Geert Uytterhoeven2015-03-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If CONFIG_SMP=n, <linux/smp.h> does not include <asm/smp.h>, causing: drivers/cpufreq/ppc-corenet-cpufreq.c: In function 'corenet_cpufreq_cpu_init': drivers/cpufreq/ppc-corenet-cpufreq.c:173:3: error: implicit declaration of function 'get_hard_smp_processor_id' [-Werror=implicit-funcuresh E. Warrier" <warrier@linux.vnet.ibm.com> X-Patchwork-Id: 443703 Message-Id: <54EE5989.7010800@linux.vnet.ibm.com> To: linuxppc-dev@ozlabs.org Date: Wed, 25 Feb 2015 17:23:53 -0600 Export __spin_yield so that the arch_spin_unlock() function can be invoked from a module. This will be required for modules where we want to take a lock that is also is acquired in hypervisor real mode. Because we want to avoid running any lockdep code (which may not be safe in real mode), this lock needs to be an arch_spinlock_t instead of a normal spinlock. Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com> Acked-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * powerpc: Remove duplicate cacheable_memcpy/memzero functionsKyle Moffett2015-03-17
| | | | | | | | | | | | | | | | | | | | | | | | These functions are only used from one place each. If the cacheable_* versions really are more efficient, then those changes should be migrated into the common code instead. NOTE: The old routines are just flat buggy on kernels that support hardware with different cacheline sizes. Signed-off-by: Kyle Moffett <Kyle.D.Moffett@boeing.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* | powerpc: Delete unnecessary checks before kfree()Markus Elfring2015-03-16
| | | | | | | | | | | | | | | | | | | | The kfree() function tests whether its argument is NULL and then returns immediately. Thus the test around the call is not needed. This issue was detected by using the Coccinelle software. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | powerpc: Change vsrX register defines to vsX to match gcc and glibcAnton Blanchard2015-03-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As our various loops (copy, string, crypto etc) get more complicated, we want to share implementations between userspace (eg glibc) and the kernel. We also want to write userspace test harnesses to put in tools/testing/selftest. One gratuitous difference between userspace and the kernel is the VSX register definitions - the kernel uses vsrX whereas gcc uses vsX. Change the kernel to match userspace. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | powerpc: Change vrX register defines to vX to match gcc and glibcAnton Blanchard2015-03-16
|/ | | | | | | | | | | | | | | | As our various loops (copy, string, crypto etc) get more complicated, we want to share implementations between userspace (eg glibc) and the kernel. We also want to write userspace test harnesses to put in tools/testing/selftest. One gratuitous difference between userspace and the kernel is the VMX register definitions - the kernel uses vrX whereas both gcc and glibc use vX. Change the kernel to match userspace. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/lib: Makefile, use obj64-y to consolidate 64-bit rulesMichael Ellerman2015-01-28
| | | | Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/lib: Makefile, consolidate obj-y sectionsMichael Ellerman2015-01-28
| | | | Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc: Add 64bit optimised memcmpAnton Blanchard2015-01-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I noticed ksm spending quite a lot of time in memcmp on a large KVM box. The current memcmp loop is very unoptimised - byte at a time compares with no loop unrolling. We can do much much better. Optimise the loop in a few ways: - Unroll the byte at a time loop - For large (at least 32 byte) comparisons that are also 8 byte aligned, use an unrolled modulo scheduled loop using 8 byte loads. This is similar to our glibc memcmp. A simple microbenchmark testing 10000000 iterations of an 8192 byte memcmp was used to measure the performance: baseline: 29.93 s modified: 1.70 s Just over 17x faster. v2: Incorporated some suggestions from Segher: - Use andi. instead of rdlicl. - Convert bdnzt eq, to bdnz. It's just duplicating the earlier compare and was a relic from a previous version. - Don't use cr5, we have plans to use that CR field for fast local atomics. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/lib: Do not include string.o in obj-y twiceAndreas Ruprecht2014-12-29
| | | | | | | | | | | | | | In the Makefile, string.o (which is generated from string.S) is included into the list of objects being built unconditionally (obj-y) in line 12. Additionally, if CONFIG_PPC64 is set, it is included again in line 17. This patch removes the latter unnecessary inclusion. Signed-off-by: Andreas Ruprecht <rupran@einserver.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* Merge branch 'for-linus' of ↵Linus Torvalds2014-12-12
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial tree update from Jiri Kosina: "Usual stuff: documentation updates, printk() fixes, etc" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (24 commits) intel_ips: fix a type in error message cpufreq: cpufreq-dt: Move newline to end of error message ps3rom: fix error return code treewide: fix typo in printk and Kconfig ARM: dts: bcm63138: change "interupts" to "interrupts" Replace mentions of "list_struct" to "list_head" kernel: trace: fix printk message scsi: mpt2sas: fix ioctl in comment zbud, zswap: change module author email clocksource: Fix 'clcoksource' typo in comment arm: fix wording of "Crotex" in CONFIG_ARCH_EXYNOS3 help gpio: msm-v1: make boolean argument more obvious usb: Fix typo in usb-serial-simple.c PCI: Fix comment typo 'COMFIG_PM_OPS' powerpc: Fix comment typo 'CONIFG_8xx' powerpc: Fix comment typos 'CONFiG_ALTIVEC' clk: st: Spelling s/stucture/structure/ isci: Spelling s/stucture/structure/ usb: gadget: zero: Spelling s/infrastucture/infrastructure/ treewide: Fix company name in module descriptions ...
| * Merge Linus' tree to be be to apply submitted patches to newer code thanJiri Kosina2014-11-20
| |\ | | | | | | | | | current trivial.git base
| * | powerpc: Fix comment typos 'CONFiG_ALTIVEC'Paul Bolle2014-10-29
| | | | | | | | | | | | | | | Signed-off-by: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* | | powerpc: Remove more traces of bootmemMichael Ellerman2014-11-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Although we are now selecting NO_BOOTMEM, we still have some traces of bootmem lying around. That is because even with NO_BOOTMEM there is still a shim that converts bootmem calls into memblock calls, but ultimately we want to remove all traces of bootmem. Most of the patch is conversions from alloc_bootmem() to memblock_virt_alloc(). In general a call such as: p = (struct foo *)alloc_bootmem(x); Becomes: p = memblock_virt_alloc(x, 0); We don't need the cast because memblock_virt_alloc() returns a void *. The alignment value of zero tells memblock to use the default alignment, which is SMP_CACHE_BYTES, the same value alloc_bootmem() uses. We remove a number of NULL checks on the result of memblock_virt_alloc(). That is because memblock_virt_alloc() will panic if it can't allocate, in exactly the same way as alloc_bootmem(), so the NULL checks are and always have been redundant. The memory returned by memblock_virt_alloc() is already zeroed, so we remove several memsets of the result of memblock_virt_alloc(). Finally we convert a few uses of __alloc_bootmem(x, y, MAX_DMA_ADDRESS) to just plain memblock_virt_alloc(). We don't use memblock_alloc_base() because MAX_DMA_ADDRESS is ~0ul on powerpc, so limiting the allocation to that is pointless, 16XB ought to be enough for anyone. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | | powerpc: Fix compilation of emulate_step()Paul Mackerras2014-11-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit be96f63375a1 ("powerpc: Split out instruction analysis part of emulate_step()") added some calls to do_fp_load() and do_fp_store(), which fail to compile on configs with CONFIG_PPC_FPU=n and CONFIG_PPC_EMULATE_SSTEP=y. This fixes the compile by adding #ifdef CONFIG_PPC_FPU around the code that calls these functions. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | | powerpc: Remove unused devm_ioremap_prot()Kyle McMartin2014-11-10
| |/ |/| | | | | | | | | | | | | Added in 2008, but has never had any in-tree users, and no other architectures provide it. Signed-off-by: Kyle McMartin <kyle@redhat.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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