summaryrefslogtreecommitdiff
path: root/arch/powerpc
AgeCommit message (Collapse)Author
2018-09-26powerpc/powernv: opal_put_chars partial write fixNicholas Piggin
[ Upstream commit bd90284cc6c1c9e8e48c8eadd0c79574fcce0b81 ] The intention here is to consume and discard the remaining buffer upon error. This works if there has not been a previous partial write. If there has been, then total_len is no longer total number of bytes to copy. total_len is always "bytes left to copy", so it should be added to written bytes. This code may not be exercised any more if partial writes will not be hit, but this is a small bugfix before a larger change. Reviewed-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-15powerpc/pseries: Avoid using the size greater than RTAS_ERROR_LOG_MAX.Mahesh Salgaonkar
[ Upstream commit 74e96bf44f430cf7a01de19ba6cf49b361cdfd6e ] The global mce data buffer that used to copy rtas error log is of 2048 (RTAS_ERROR_LOG_MAX) bytes in size. Before the copy we read extended_log_length from rtas error log header, then use max of extended_log_length and RTAS_ERROR_LOG_MAX as a size of data to be copied. Ideally the platform (phyp) will never send extended error log with size > 2048. But if that happens, then we have a risk of buffer overrun and corruption. Fix this by using min_t instead. Fixes: d368514c3097 ("powerpc: Fix corruption when grabbing FWNMI data") Reported-by: Michal Suchanek <msuchanek@suse.com> Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-15powerpc: Fix size calculation using resource_size()Dan Carpenter
[ Upstream commit c42d3be0c06f0c1c416054022aa535c08a1f9b39 ] The problem is the the calculation should be "end - start + 1" but the plus one is missing in this calculation. Fixes: 8626816e905e ("powerpc: add support for MPIC message register API") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-09powerpc/powernv/pci: Work around races in PCI bridge enablingBenjamin Herrenschmidt
commit db2173198b9513f7add8009f225afa1f1c79bcc6 upstream. The generic code is racy when multiple children of a PCI bridge try to enable it simultaneously. This leads to drivers trying to access a device through a not-yet-enabled bridge, and this EEH errors under various circumstances when using parallel driver probing. There is work going on to fix that properly in the PCI core but it will take some time. x86 gets away with it because (outside of hotplug), the BIOS enables all the bridges at boot time. This patch does the same thing on powernv by enabling all bridges that have child devices at boot time, thus avoiding subsequent races. It's suitable for backporting to stable and distros, while the proper PCI fix will probably be significantly more invasive. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: stable@vger.kernel.org Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-09powerpc/pseries: Fix endianness while restoring of r3 in MCE handler.Mahesh Salgaonkar
commit cd813e1cd7122f2c261dce5b54d1e0c97f80e1a5 upstream. During Machine Check interrupt on pseries platform, register r3 points RTAS extended event log passed by hypervisor. Since hypervisor uses r3 to pass pointer to rtas log, it stores the original r3 value at the start of the memory (first 8 bytes) pointed by r3. Since hypervisor stores this info and rtas log is in BE format, linux should make sure to restore r3 value in correct endian format. Without this patch when MCE handler, after recovery, returns to code that that caused the MCE may end up with Data SLB access interrupt for invalid address followed by kernel panic or hang. Severe Machine check interrupt [Recovered] NIP [d00000000ca301b8]: init_module+0x1b8/0x338 [bork_kernel] Initiator: CPU Error type: SLB [Multihit] Effective address: d00000000ca70000 cpu 0xa: Vector: 380 (Data SLB Access) at [c0000000fc7775b0] pc: c0000000009694c0: vsnprintf+0x80/0x480 lr: c0000000009698e0: vscnprintf+0x20/0x60 sp: c0000000fc777830 msr: 8000000002009033 dar: a803a30c000000d0 current = 0xc00000000bc9ef00 paca = 0xc00000001eca5c00 softe: 3 irq_happened: 0x01 pid = 8860, comm = insmod vscnprintf+0x20/0x60 vprintk_emit+0xb4/0x4b0 vprintk_func+0x5c/0xd0 printk+0x38/0x4c init_module+0x1c0/0x338 [bork_kernel] do_one_initcall+0x54/0x230 do_init_module+0x8c/0x248 load_module+0x12b8/0x15b0 sys_finit_module+0xa8/0x110 system_call+0x58/0x6c --- Exception: c00 (System Call) at 00007fff8bda0644 SP (7fffdfbfe980) is in userspace This patch fixes this issue. Fixes: a08a53ea4c97 ("powerpc/le: Enable RTAS events support") Cc: stable@vger.kernel.org # v3.15+ Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-09powerpc/fadump: handle crash memory ranges array index overflowHari Bathini
commit 1bd6a1c4b80a28d975287630644e6b47d0f977a5 upstream. Crash memory ranges is an array of memory ranges of the crashing kernel to be exported as a dump via /proc/vmcore file. The size of the array is set based on INIT_MEMBLOCK_REGIONS, which works alright in most cases where memblock memory regions count is less than INIT_MEMBLOCK_REGIONS value. But this count can grow beyond INIT_MEMBLOCK_REGIONS value since commit 142b45a72e22 ("memblock: Add array resizing support"). On large memory systems with a few DLPAR operations, the memblock memory regions count could be larger than INIT_MEMBLOCK_REGIONS value. On such systems, registering fadump results in crash or other system failures like below: task: c00007f39a290010 ti: c00000000b738000 task.ti: c00000000b738000 NIP: c000000000047df4 LR: c0000000000f9e58 CTR: c00000000010f180 REGS: c00000000b73b570 TRAP: 0300 Tainted: G L X (4.4.140+) MSR: 8000000000009033 <SF,EE,ME,IR,DR,RI,LE> CR: 22004484 XER: 20000000 CFAR: c000000000008500 DAR: 000007a450000000 DSISR: 40000000 SOFTE: 0 ... NIP [c000000000047df4] smp_send_reschedule+0x24/0x80 LR [c0000000000f9e58] resched_curr+0x138/0x160 Call Trace: resched_curr+0x138/0x160 (unreliable) check_preempt_curr+0xc8/0xf0 ttwu_do_wakeup+0x38/0x150 try_to_wake_up+0x224/0x4d0 __wake_up_common+0x94/0x100 ep_poll_callback+0xac/0x1c0 __wake_up_common+0x94/0x100 __wake_up_sync_key+0x70/0xa0 sock_def_readable+0x58/0xa0 unix_stream_sendmsg+0x2dc/0x4c0 sock_sendmsg+0x68/0xa0 ___sys_sendmsg+0x2cc/0x2e0 __sys_sendmsg+0x5c/0xc0 SyS_socketcall+0x36c/0x3f0 system_call+0x3c/0x100 as array index overflow is not checked for while setting up crash memory ranges causing memory corruption. To resolve this issue, dynamically allocate memory for crash memory ranges and resize it incrementally, in units of pagesize, on hitting array size limit. Fixes: 2df173d9e85d ("fadump: Initialize elfcore header and add PT_LOAD program headers.") Cc: stable@vger.kernel.org # v3.4+ Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> [mpe: Just use PAGE_SIZE directly, fixup variable placement] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05bpf, ppc64: fix unexpected r0=0 exit path inside bpf_xaddDaniel Borkmann
[ Upstream commit b9c1e60e7bf4e64ac1b4f4d6d593f0bb57886973 ] None of the JITs is allowed to implement exit paths from the BPF insn mappings other than BPF_JMP | BPF_EXIT. In the BPF core code we have a couple of rewrites in eBPF (e.g. LD_ABS / LD_IND) and in eBPF to cBPF translation to retain old existing behavior where exceptions may occur; they are also tightly controlled by the verifier where it disallows some of the features such as BPF to BPF calls when legacy LD_ABS / LD_IND ops are present in the BPF program. During recent review of all BPF_XADD JIT implementations I noticed that the ppc64 one is buggy in that it contains two jumps to exit paths. This is problematic as this can bypass verifier expectations e.g. pointed out in commit f6b1b3bf0d5f ("bpf: fix subprog verifier bypass by div/mod by 0 exception"). The first exit path is obsoleted by the fix in ca36960211eb ("bpf: allow xadd only on aligned memory") anyway, and for the second one we need to do a fetch, add and store loop if the reservation from lwarx/ldarx was lost in the meantime. Fixes: 156d0e290e96 ("powerpc/ebpf/jit: Implement JIT compiler for extended BPF") Reviewed-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Reviewed-by: Sandipan Das <sandipan@linux.vnet.ibm.com> Tested-by: Sandipan Das <sandipan@linux.vnet.ibm.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-03powerpc/embedded6xx/hlwd-pic: Prevent interrupts from being handled by StarletJonathan Neuschäfer
[ Upstream commit 9dcb3df4281876731e4e8bff7940514d72375154 ] The interrupt controller inside the Wii's Hollywood chip is connected to two masters, the "Broadway" PowerPC and the "Starlet" ARM926, each with their own interrupt status and mask registers. When booting the Wii with mini[1], interrupts from the SD card controller (IRQ 7) are handled by the ARM, because mini provides SD access over IPC. Linux however can't currently use or disable this IPC service, so both sides try to handle IRQ 7 without coordination. Let's instead make sure that all interrupts that are unmasked on the PPC side are masked on the ARM side; this will also make sure that Linux can properly talk to the SD card controller (and potentially other devices). If access to a device through IPC is desired in the future, interrupts from that device should not be handled by Linux directly. [1]: https://github.com/lewurm/mini Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-03bpf: powerpc64: pad function address loads with NOPsSandipan Das
[ Upstream commit 4ea69b2fd623dee2bbc77d3b6b7d8c0924e2026a ] For multi-function programs, loading the address of a callee function to a register requires emitting instructions whose count varies from one to five depending on the nature of the address. Since we come to know of the callee's address only before the extra pass, the number of instructions required to load this address may vary from what was previously generated. This can make the JITed image grow or shrink. To avoid this, we should generate a constant five-instruction when loading function addresses by padding the optimized load sequence with NOPs. Signed-off-by: Sandipan Das <sandipan@linux.vnet.ibm.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-03powerpc/8xx: fix invalid register expression in head_8xx.SChristophe Leroy
[ Upstream commit e4ccb1dae6bdef228d729c076c38161ef6e7ca34 ] New binutils generate the following warning AS arch/powerpc/kernel/head_8xx.o arch/powerpc/kernel/head_8xx.S: Assembler messages: arch/powerpc/kernel/head_8xx.S:916: Warning: invalid register expression This patch fixes it. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-03powerpc/powermac: Mark variable x as unusedMathieu Malaterre
[ Upstream commit 5a4b475cf8511da721f20ba432c244061db7139f ] Since the value of x is never intended to be read, declare it with gcc attribute as unused. Fix warning treated as error with W=1: arch/powerpc/platforms/powermac/bootx_init.c:471:21: error: variable ‘x’ set but not used [-Werror=unused-but-set-variable] Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Mathieu Malaterre <malat@debian.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-03powerpc/powermac: Add missing prototype for note_bootable_part()Mathieu Malaterre
[ Upstream commit f72cf3f1d49f2c35d6cb682af2e8c93550f264e4 ] Add a missing prototype for function `note_bootable_part` to silence a warning treated as error with W=1: arch/powerpc/platforms/powermac/setup.c:361:12: error: no previous prototype for ‘note_bootable_part’ [-Werror=missing-prototypes] Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Mathieu Malaterre <malat@debian.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-03powerpc/chrp/time: Make some functions static, add missing header includeMathieu Malaterre
[ Upstream commit b87a358b4a1421abd544c0b554b1b7159b2b36c0 ] Add a missing include <platforms/chrp/chrp.h>. These functions can all be static, make it so. Fix warnings treated as errors with W=1: arch/powerpc/platforms/chrp/time.c:41:13: error: no previous prototype for ‘chrp_time_init’ [-Werror=missing-prototypes] arch/powerpc/platforms/chrp/time.c:66:5: error: no previous prototype for ‘chrp_cmos_clock_read’ [-Werror=missing-prototypes] arch/powerpc/platforms/chrp/time.c:74:6: error: no previous prototype for ‘chrp_cmos_clock_write’ [-Werror=missing-prototypes] arch/powerpc/platforms/chrp/time.c:86:5: error: no previous prototype for ‘chrp_set_rtc_time’ [-Werror=missing-prototypes] arch/powerpc/platforms/chrp/time.c:130:6: error: no previous prototype for ‘chrp_get_rtc_time’ [-Werror=missing-prototypes] Signed-off-by: Mathieu Malaterre <malat@debian.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-03powerpc/32: Add a missing include headerMathieu Malaterre
[ Upstream commit c89ca593220931c150cffda24b4d4ccf82f13fc8 ] The header file <linux/syscalls.h> was missing from the includes. Fix the following warning, treated as error with W=1: arch/powerpc/kernel/pci_32.c:286:6: error: no previous prototype for ‘sys_pciconfig_iobase’ [-Werror=missing-prototypes] Signed-off-by: Mathieu Malaterre <malat@debian.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-03powerpc/64s: Fix compiler store ordering to SLB shadow areaNicholas Piggin
[ Upstream commit 926bc2f100c24d4842b3064b5af44ae964c1d81c ] The stores to update the SLB shadow area must be made as they appear in the C code, so that the hypervisor does not see an entry with mismatched vsid and esid. Use WRITE_ONCE for this. GCC has been observed to elide the first store to esid in the update, which means that if the hypervisor interrupts the guest after storing to vsid, it could see an entry with old esid and new vsid, which may possibly result in memory corruption. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-03powerpc/eeh: Fix use-after-release of EEH driverSam Bobroff
[ Upstream commit 46d4be41b987a6b2d25a2ebdd94cafb44e21d6c5 ] Correct two cases where eeh_pcid_get() is used to reference the driver's module but the reference is dropped before the driver pointer is used. In eeh_rmv_device() also refactor a little so that only two calls to eeh_pcid_put() are needed, rather than three and the reference isn't taken at all if it wasn't needed. Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-03powerpc/fadump: Unregister fadump on kexec down path.Mahesh Salgaonkar
commit 722cde76d68e8cc4f3de42e71c82fd40dea4f7b9 upstream. Unregister fadump on kexec down path otherwise the fadump registration in new kexec-ed kernel complains that fadump is already registered. This makes new kernel to continue using fadump registered by previous kernel which may lead to invalid vmcore generation. Hence this patch fixes this issue by un-registering fadump in fadump_cleanup() which is called during kexec path so that new kernel can register fadump with new valid values. Fixes: b500afff11f6 ("fadump: Invalidate registration and release reserved memory for general use.") Cc: stable@vger.kernel.org # v3.4+ Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-03powerpc/powernv/ioda2: Remove redundant free of TCE pagesAlexey Kardashevskiy
commit 98fd72fe82527fd26618062b60cfd329451f2329 upstream. When IODA2 creates a PE, it creates an IOMMU table with it_ops::free set to pnv_ioda2_table_free() which calls pnv_pci_ioda2_table_free_pages(). Since iommu_tce_table_put() calls it_ops::free when the last reference to the table is released, explicit call to pnv_pci_ioda2_table_free_pages() is not needed so let's remove it. This should fix double free in the case of PCI hotuplug as pnv_pci_ioda2_table_free_pages() does not reset neither iommu_table::it_base nor ::it_size. This was not exposed by SRIOV as it uses different code path via pnv_pcibios_sriov_disable(). IODA1 does not inialize it_ops::free so it does not have this issue. Fixes: c5f7700bbd2e ("powerpc/powernv: Dynamically release PE") Cc: stable@vger.kernel.org # v4.8+ Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-03powerpc/ptrace: Fix enforcement of DAWR constraintsMichael Neuling
commit cd6ef7eebf171bfcba7dc2df719c2a4958775040 upstream. Back when we first introduced the DAWR, in commit 4ae7ebe9522a ("powerpc: Change hardware breakpoint to allow longer ranges"), we screwed up the constraint making it a 1024 byte boundary rather than a 512. This makes the check overly permissive. Fortunately GDB is the only real user and it always did they right thing, so we never noticed. This fixes the constraint to 512 bytes. Fixes: 4ae7ebe9522a ("powerpc: Change hardware breakpoint to allow longer ranges") Cc: stable@vger.kernel.org # v3.9+ Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-03powerpc/ptrace: Fix setting 512B aligned breakpoints with PTRACE_SET_DEBUGREGMichael Neuling
commit 4f7c06e26ec9cf7fe9f0c54dc90079b6a4f4b2c3 upstream. In commit e2a800beaca1 ("powerpc/hw_brk: Fix off by one error when validating DAWR region end") we fixed setting the DAWR end point to its max value via PPC_PTRACE_SETHWDEBUG. Unfortunately we broke PTRACE_SET_DEBUGREG when setting a 512 byte aligned breakpoint. PTRACE_SET_DEBUGREG currently sets the length of the breakpoint to zero (memset() in hw_breakpoint_init()). This worked with arch_validate_hwbkpt_settings() before the above patch was applied but is now broken if the breakpoint is 512byte aligned. This sets the length of the breakpoint to 8 bytes when using PTRACE_SET_DEBUGREG. Fixes: e2a800beaca1 ("powerpc/hw_brk: Fix off by one error when validating DAWR region end") Cc: stable@vger.kernel.org # v3.11+ Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-03powerpc/mm/hash: Add missing isync prior to kernel stack SLB switchAneesh Kumar K.V
commit 91d06971881f71d945910de128658038513d1b24 upstream. Currently we do not have an isync, or any other context synchronizing instruction prior to the slbie/slbmte in _switch() that updates the SLB entry for the kernel stack. However that is not correct as outlined in the ISA. From Power ISA Version 3.0B, Book III, Chapter 11, page 1133: "Changing the contents of ... the contents of SLB entries ... can have the side effect of altering the context in which data addresses and instruction addresses are interpreted, and in which instructions are executed and data accesses are performed. ... These side effects need not occur in program order, and therefore may require explicit synchronization by software. ... The synchronizing instruction before the context-altering instruction ensures that all instructions up to and including that synchronizing instruction are fetched and executed in the context that existed before the alteration." And page 1136: "For data accesses, the context synchronizing instruction before the slbie, slbieg, slbia, slbmte, tlbie, or tlbiel instruction ensures that all preceding instructions that access data storage have completed to a point at which they have reported all exceptions they will cause." We're not aware of any bugs caused by this, but it should be fixed regardless. Add the missing isync when updating kernel stack SLB entry. Cc: stable@vger.kernel.org Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> [mpe: Flesh out change log with more ISA text & explanation] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-06powerpc/64s: Add support for a store forwarding barrier at kernel entry/exitNicholas Piggin
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> 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>
2018-06-06powerpc/64s: Fix section mismatch warnings from setup_rfi_flush()Michael Ellerman
commit 501a78cbc17c329fabf8e9750a1e9ab810c88a0e upstream. The recent LPM changes to setup_rfi_flush() are causing some section mismatch warnings because we removed the __init annotation on setup_rfi_flush(): The function setup_rfi_flush() references the function __init ppc64_bolted_size(). the function __init memblock_alloc_base(). The references are actually in init_fallback_flush(), but that is inlined into setup_rfi_flush(). These references are safe because: - only pseries calls setup_rfi_flush() at runtime - pseries always passes L1D_FLUSH_FALLBACK at boot - so the fallback flush area will always be allocated - so the check in init_fallback_flush() will always return early: /* Only allocate the fallback flush area once (at boot time). */ if (l1d_flush_fallback_area) return; - and therefore we won't actually call the freed init routines. We should rework the code to make it safer by default rather than relying on the above, but for now as a quick-fix just add a __ref annotation to squash the warning. Fixes: abf110f3e1ce ("powerpc/rfi-flush: Make it possible to call setup_rfi_flush() again") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-06powerpc/pseries: Restore default security feature flags on setupMauricio Faria de Oliveira
commit 6232774f1599028a15418179d17f7df47ede770a upstream. After migration the security feature flags might have changed (e.g., destination system with unpatched firmware), but some flags are not set/clear again in init_cpu_char_feature_flags() because it assumes the security flags to be the defaults. Additionally, if the H_GET_CPU_CHARACTERISTICS hypercall fails then init_cpu_char_feature_flags() does not run again, which potentially might leave the system in an insecure or sub-optimal configuration. So, just restore the security feature flags to the defaults assumed by init_cpu_char_feature_flags() so it can set/clear them correctly, and to ensure safe settings are in place in case the hypercall fail. Fixes: f636c14790ea ("powerpc/pseries: Set or clear security feature flags") Depends-on: 19887d6a28e2 ("powerpc: Move default security feature flags") 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>
2018-06-06powerpc: Move default security feature flagsMauricio Faria de Oliveira
commit e7347a86830f38dc3e40c8f7e28c04412b12a2e7 upstream. This moves the definition of the default security feature flags (i.e., enabled by default) closer to the security feature flags. This can be used to restore current flags to the default flags. 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>
2018-06-06powerpc/pseries: Fix clearing of security feature flagsMauricio Faria de Oliveira
commit 0f9bdfe3c77091e8704d2e510eb7c2c2c6cde524 upstream. The H_CPU_BEHAV_* flags should be checked for in the 'behaviour' field of 'struct h_cpu_char_result' -- 'character' is for H_CPU_CHAR_* flags. Found by playing around with QEMU's implementation of the hypercall: H_CPU_CHAR=0xf000000000000000 H_CPU_BEHAV=0x0000000000000000 This clears H_CPU_BEHAV_FAVOUR_SECURITY and H_CPU_BEHAV_L1D_FLUSH_PR so pseries_setup_rfi_flush() disables 'rfi_flush'; and it also clears H_CPU_CHAR_L1D_THREAD_PRIV flag. So there is no RFI flush mitigation at all for cpu_show_meltdown() to report; but currently it does: Original kernel: # cat /sys/devices/system/cpu/vulnerabilities/meltdown Mitigation: RFI Flush Patched kernel: # cat /sys/devices/system/cpu/vulnerabilities/meltdown Not affected H_CPU_CHAR=0x0000000000000000 H_CPU_BEHAV=0xf000000000000000 This sets H_CPU_BEHAV_BNDS_CHK_SPEC_BAR so cpu_show_spectre_v1() should report vulnerable; but currently it doesn't: Original kernel: # cat /sys/devices/system/cpu/vulnerabilities/spectre_v1 Not affected Patched kernel: # cat /sys/devices/system/cpu/vulnerabilities/spectre_v1 Vulnerable Brown-paper-bag-by: Michael Ellerman <mpe@ellerman.id.au> Fixes: f636c14790ea ("powerpc/pseries: Set or clear security feature flags") 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>
2018-06-06powerpc/64s: Wire up cpu_show_spectre_v2()Michael Ellerman
commit d6fbe1c55c55c6937cbea3531af7da84ab7473c3 upstream. Add a definition for cpu_show_spectre_v2() to override the generic version. This has several permuations, though in practice some may not occur we cater for any combination. The most verbose is: Mitigation: Indirect branch serialisation (kernel only), Indirect branch cache disabled, ori31 speculation barrier enabled We don't treat the ori31 speculation barrier as a mitigation on its own, because it has to be *used* by code in order to be a mitigation and we don't know if userspace is doing that. So if that's all we see we say: Vulnerable, ori31 speculation barrier enabled Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-06powerpc/64s: Wire up cpu_show_spectre_v1()Michael Ellerman
commit 56986016cb8cd9050e601831fe89f332b4e3c46e upstream. Add a definition for cpu_show_spectre_v1() to override the generic version. Currently this just prints "Not affected" or "Vulnerable" based on the firmware flag. Although the kernel does have array_index_nospec() in a few places, we haven't yet audited all the powerpc code to see where it's necessary, so for now we don't list that as a mitigation. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-06powerpc/pseries: Use the security flags in pseries_setup_rfi_flush()Michael Ellerman
commit 2e4a16161fcd324b1f9bf6cb6856529f7eaf0689 upstream. Now that we have the security flags we can simplify the code in pseries_setup_rfi_flush() because the security flags have pessimistic defaults. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-06powerpc/powernv: Use the security flags in pnv_setup_rfi_flush()Michael Ellerman
commit 37c0bdd00d3ae83369ab60a6712c28e11e6458d5 upstream. Now that we have the security flags we can significantly simplify the code in pnv_setup_rfi_flush(), because we can use the flags instead of checking device tree properties and because the security flags have pessimistic defaults. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-06powerpc/64s: Enhance the information in cpu_show_meltdown()Michael Ellerman
commit ff348355e9c72493947be337bb4fae4fc1a41eba upstream. Now that we have the security feature flags we can make the information displayed in the "meltdown" file more informative. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-06powerpc/64s: Move cpu_show_meltdown()Michael Ellerman
commit 8ad33041563a10b34988800c682ada14b2612533 upstream. This landed in setup_64.c for no good reason other than we had nowhere else to put it. Now that we have a security-related file, that is a better place for it so move it. [mpe: Add extern for rfi_flush to fix bisection break] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-06powerpc/powernv: Set or clear security feature flagsMichael Ellerman
commit 77addf6e95c8689e478d607176b399a6242a777e upstream. Now that we have feature flags for security related things, set or clear them based on what we see in the device tree provided by firmware. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-06powerpc/pseries: Set or clear security feature flagsMichael Ellerman
commit f636c14790ead6cc22cf62279b1f8d7e11a67116 upstream. Now that we have feature flags for security related things, set or clear them based on what we receive from the hypercall. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-06powerpc: Add security feature flags for Spectre/MeltdownMichael Ellerman
commit 9a868f634349e62922c226834aa23e3d1329ae7f upstream. This commit adds security feature flags to reflect the settings we receive from firmware regarding Spectre/Meltdown mitigations. The feature names reflect the names we are given by firmware on bare metal machines. See the hostboot source for details. Arguably these could be firmware features, but that then requires them to be read early in boot so they're available prior to asm feature patching, but we don't actually want to use them for patching. We may also want to dynamically update them in future, which would be incompatible with the way firmware features work (at the moment at least). So for now just make them separate flags. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-06powerpc/pseries: Add new H_GET_CPU_CHARACTERISTICS flagsMichael Ellerman
commit c4bc36628d7f8b664657d8bd6ad1c44c177880b7 upstream. Add some additional values which have been defined for the H_GET_CPU_CHARACTERISTICS hypercall. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-06powerpc/rfi-flush: Call setup_rfi_flush() after LPM migrationMichael Ellerman
commit 921bc6cf807ceb2ab8005319cf39f33494d6b100 upstream. We might have migrated to a machine that uses a different flush type, or doesn't need flushing at all. Signed-off-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>
2018-06-06powerpc/rfi-flush: Differentiate enabled and patched flush typesMauricio Faria de Oliveira
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>
2018-06-06powerpc/rfi-flush: Always enable fallback flush on pseriesMichael Ellerman
commit 84749a58b6e382f109abf1e734bc4dd43c2c25bb upstream. This ensures the fallback flush area is always allocated on pseries, so in case a LPAR is migrated from a patched to an unpatched system, it is possible to enable the fallback flush in the target system. Signed-off-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>
2018-06-06powerpc/rfi-flush: Make it possible to call setup_rfi_flush() againMichael Ellerman
commit abf110f3e1cea40f5ea15e85f5d67c39c14568a7 upstream. For PowerVM migration we want to be able to call setup_rfi_flush() again after we've migrated the partition. To support that we need to check that we're not trying to allocate the fallback flush area after memblock has gone away (i.e., boot-time only). Signed-off-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>
2018-06-06powerpc/rfi-flush: Move the logic to avoid a redo into the debugfs codeMichael Ellerman
commit 1e2a9fc7496955faacbbed49461d611b704a7505 upstream. rfi_flush_enable() includes a check to see if we're already enabled (or disabled), and in that case does nothing. But that means calling setup_rfi_flush() a 2nd time doesn't actually work, which is a bit confusing. Move that check into the debugfs code, where it really belongs. Signed-off-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>
2018-06-06powerpc/powernv: Support firmware disable of RFI flushMichael Ellerman
commit eb0a2d2620ae431c543963c8c7f08f597366fc60 upstream. Some versions of firmware will have a setting that can be configured to disable the RFI flush, add support for it. Fixes: 6e032b350cd1 ("powerpc/powernv: Check device-tree for RFI flush settings") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-06powerpc/pseries: Support firmware disable of RFI flushMichael Ellerman
commit 582605a429e20ae68fd0b041b2e840af296edd08 upstream. Some versions of firmware will have a setting that can be configured to disable the RFI flush, add support for it. Fixes: 8989d56878a7 ("powerpc/pseries: Query hypervisor for RFI flush settings") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-06powerpc/rfi-flush: Move out of HARDLOCKUP_DETECTOR #ifdefMichael Ellerman
The backport of the RFI flush support, done by me, has a minor bug in that the code is inside an #ifdef CONFIG_HARDLOCKUP_DETECTOR, which is incorrect. This doesn't matter with common configs because we enable HARDLOCKUP_DETECTOR, but with future patches it will break the build. So fix it. Fixes: c3b82ebee6e0 ("powerpc/64s: Add support for RFI flush of L1-D cache") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-06powerpc/64s: Clear PCR on bootMichael Neuling
commit faf37c44a105f3608115785f17cbbf3500f8bc71 upstream. Clear the PCR (Processor Compatibility Register) on boot to ensure we are not running in a compatibility mode. We've seen this cause problems when a crash (and kdump) occurs while running compat mode guests. The kdump kernel then runs with the PCR set and causes problems. The symptom in the kdump kernel (also seen in petitboot after fast-reboot) is early userspace programs taking sigills on newer instructions (seen in libc). Signed-off-by: Michael Neuling <mikey@neuling.org> Cc: stable@vger.kernel.org Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30powerpc: Add missing prototype for arch_irq_work_raise()Mathieu Malaterre
[ Upstream commit f5246862f82f1e16bbf84cda4cddf287672b30fe ] In commit 4f8b50bbbe63 ("irq_work, ppc: Fix up arch hooks") a new function arch_irq_work_raise() was added without a prototype in header irq_work.h. Fix the following warning (treated as error in W=1): arch/powerpc/kernel/time.c:523:6: error: no previous prototype for ‘arch_irq_work_raise’ Signed-off-by: Mathieu Malaterre <malat@debian.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30powerpc/perf: Fix kernel address leak via sampling registersMichael Ellerman
[ Upstream commit e1ebd0e5b9d0a10ba65e63a3514b6da8c6a5a819 ] Current code in power_pmu_disable() does not clear the sampling registers like Sampling Instruction Address Register (SIAR) and Sampling Data Address Register (SDAR) after disabling the PMU. Since these are userspace readable and could contain kernel addresses, add code to explicitly clear the content of these registers. Also add a "context synchronizing instruction" to enforce no further updates to these registers as suggested by Power ISA v3.0B. From section 9.4, on page 1108: "If an mtspr instruction is executed that changes the value of a Performance Monitor register other than SIAR, SDAR, and SIER, the change is not guaranteed to have taken effect until after a subsequent context synchronizing instruction has been executed (see Chapter 11. "Synchronization Requirements for Context Alterations" on page 1133)." Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com> [mpe: Massage change log and add ISA reference] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30powerpc/perf: Prevent kernel address leak to userspace via BHRB bufferMadhavan Srinivasan
[ Upstream commit bb19af816025d495376bd76bf6fbcf4244f9a06d ] The current Branch History Rolling Buffer (BHRB) code does not check for any privilege levels before updating the data from BHRB. This could leak kernel addresses to userspace even when profiling only with userspace privileges. Add proper checks to prevent it. Acked-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30powerpc/mpic: Check if cpu_possible() in mpic_physmask()Michael Ellerman
[ Upstream commit 0834d627fbea00c1444075eb3e448e1974da452d ] In mpic_physmask() we loop over all CPUs up to 32, then get the hard SMP processor id of that CPU. Currently that's possibly walking off the end of the paca array, but in a future patch we will change the paca array to be an array of pointers, and in that case we will get a NULL for missing CPUs and oops. eg: Unable to handle kernel paging request for data at address 0x88888888888888b8 Faulting instruction address: 0xc00000000004e380 Oops: Kernel access of bad area, sig: 11 [#1] ... NIP .mpic_set_affinity+0x60/0x1a0 LR .irq_do_set_affinity+0x48/0x100 Fix it by checking the CPU is possible, this also fixes the code if there are gaps in the CPU numbering which probably never happens on mpic systems but who knows. Debugged-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30KVM: PPC: Book3S HV: Fix VRMA initialization with 2MB or 1GB memory backingPaul Mackerras
[ Upstream commit debd574f4195e205ba505b25e19b2b797f4bcd94 ] The current code for initializing the VRMA (virtual real memory area) for HPT guests requires the page size of the backing memory to be one of 4kB, 64kB or 16MB. With a radix host we have the possibility that the backing memory page size can be 2MB or 1GB. In these cases, if the guest switches to HPT mode, KVM will not initialize the VRMA and the guest will fail to run. In fact it is not necessary that the VRMA page size is the same as the backing memory page size; any VRMA page size less than or equal to the backing memory page size is acceptable. Therefore we now choose the largest page size out of the set {4k, 64k, 16M} which is not larger than the backing memory page size. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>