Buildresult: powerpc-fixes/ia64-defconfig/ia64-gcc4.6 built on Jan 23 2020, 14:54

kisskb

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Status:	OK
Date/Time:	Jan 23 2020, 14:54
Duration:	0:03:01.070349
Builder:	ka2
Revision:	powerpc/mm/hash: Fix sharing context ids between kernel & userspace (`8a17ea07703f5f41e8c96b123f63be4eac107374)`
Target:	powerpc-fixes/ia64-defconfig/ia64-gcc4.6
Branch:	powerpc-fixes
Compiler:	ia64-gcc4.6 (ia64-linux-gcc (GCC) 4.6.3 / GNU ld (GNU Binutils) 2.22)
Config:	defconfig (download)
Log:	Download original Possible warnings (12) <stdin>:1511:2: warning: #warning syscall clone3 not implemented [-Wcpp] kernel/printk/printk.c:204:16: warning: 'old' may be used uninitialized in this function [-Wuninitialized] mm/vmstat.c:90:5: warning: 'oldval' may be used uninitialized in this function [-Wuninitialized] mm/hugetlb.c:1377:5: warning: 'page' may be used uninitialized in this function [-Wuninitialized] fs/ext4/extents.c:5054:23: warning: 'ret' may be used uninitialized in this function [-Wuninitialized] fs/nfs/read.c:196:5: warning: value computed is not used [-Wunused-value] fs/nfs/read.c:352:2: warning: value computed is not used [-Wunused-value] fs/nfsd/nfs4xdr.c:2076:9: warning: 'str' may be used uninitialized in this function [-Wuninitialized] include/linux/list.h:65:12: warning: 'pdeo' may be used uninitialized in this function [-Wuninitialized] fs/udf/unicode.c:132:8: warning: 'c' may be used uninitialized in this function [-Wuninitialized] include/linux/of_mdio.h:58:13: warning: 'of_mdiobus_child_is_phy' defined but not used [-Wunused-function] drivers/usb/core/devio.c:625:23: warning: 'errno' may be used uninitialized in this function [-Wuninitialized] Full Log # git rev-parse -q --verify 8a17ea07703f5f41e8c96b123f63be4eac107374^{commit} # git fetch -q -n -f git://gitlab.ozlabs.ibm.com/linuxppc/linux.git fixes-test # git rev-parse -q --verify 8a17ea07703f5f41e8c96b123f63be4eac107374^{commit} 8a17ea07703f5f41e8c96b123f63be4eac107374 # git checkout -q -f -B kisskb 8a17ea07703f5f41e8c96b123f63be4eac107374 # git clean -qxdf # < git log -1 # commit 8a17ea07703f5f41e8c96b123f63be4eac107374 # Author: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> # Date: Wed Jan 8 11:14:22 2020 +0530 # # powerpc/mm/hash: Fix sharing context ids between kernel & userspace # # Commit 0034d395f89d ("powerpc/mm/hash64: Map all the kernel regions in # the same 0xc range") has a bug in the definition of MIN_USER_CONTEXT. # # The result is that the context id used for the vmemmap and the lowest # context id handed out to userspace are the same. The context id is # essentially the process identifier as far as the first stage of the # MMU translation is concerned. # # This can result in multiple SLB entries with the same VSID (Virtual # Segment ID), accessible to the kernel and some random userspace # process that happens to get the overlapping id, which is not expected # eg: # # 07 c00c000008000000 40066bdea7000500 1T ESID= c00c00 VSID= 66bdea7 LLP:100 # 12 0002000008000000 40066bdea7000d80 1T ESID= 200 VSID= 66bdea7 LLP:100 # # Even though the user process and the kernel use the same VSID, the # permissions in the hash page table prevent the user process from # reading or writing to any kernel mappings. # # It can also lead to SLB entries with different base page size # encodings (LLP), eg: # # 05 c00c000008000000 00006bde0053b500 256M ESID=c00c00000 VSID= 6bde0053b LLP:100 # 09 0000000008000000 00006bde0053bc80 256M ESID= 0 VSID= 6bde0053b LLP: 0 # # Such SLB entries can result in machine checks, eg. as seen on a G5: # # Oops: Machine check, sig: 7 [#1] # BE PAGE SIZE=64K MU-Hash SMP NR_CPUS=4 NUMA Power Mac # NIP: c00000000026f248 LR: c000000000295e58 CTR: 0000000000000000 # REGS: c0000000erfd3d70 TRAP: 0200 Tainted: G M (5.5.0-rcl-gcc-8.2.0-00010-g228b667d8ea1) # MSR: 9000000000109032 <SF,HV,EE,ME,IR,DR,RI> CR: 24282048 XER: 00000000 # DAR: c00c000000612c80 DSISR: 00000400 IRQMASK: 0 # ... # NIP [c00000000026f248] .kmem_cache_free+0x58/0x140 # LR [c088000008295e58] .putname 8x88/0xa # Call Trace: # .putname+0xB8/0xa # .filename_lookup.part.76+0xbe/0x160 # .do_faccessat+0xe0/0x380 # system_call+0x5c/ex68 # # This happens with 256MB segments and 64K pages, as the duplicate VSID # is hit with the first vmemmap segment and the first user segment, and # older 32-bit userspace maps things in the first user segment. # # On other CPUs a machine check is not seen. Instead the userspace # process can get stuck continuously faulting, with the fault never # properly serviced, due to the kernel not understanding that there is # already a HPTE for the address but with inaccessible permissions. # # On machines with 1T segments we've not seen the bug hit other than by # deliberately exercising it. That seems to be just a matter of luck # though, due to the typical layout of the user virtual address space # and the ranges of vmemmap that are typically populated. # # To fix it we add 2 to MIN_USER_CONTEXT. This ensures the lowest # context given to userspace doesn't overlap with the VMEMMAP context, # or with the context for INVALID_REGION_ID. Also add some # BUILD_BUG_ON()'s to check the values. # # Fixes: 0034d395f89d ("powerpc/mm/hash64: Map all the kernel regions in the same 0xc range") # Cc: stable@vger.kernel.org # v5.2+ # Reported-by: Christian Marillat <marillat@debian.org> # Reported-by: Romain Dolbeau <romain@dolbeau.org> # Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> # [mpe: Account for INVALID_REGION_ID, mostly rewrite change log] # Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> # < /opt/cross/kisskb/gcc-4.6.3-nolibc/ia64-linux/bin/ia64-linux-gcc --version # < /opt/cross/kisskb/gcc-4.6.3-nolibc/ia64-linux/bin/ia64-linux-ld --version # < git log --format=%s --max-count=1 8a17ea07703f5f41e8c96b123f63be4eac107374 # < make -s -j 8 ARCH=ia64 O=/kisskb/build/powerpc-fixes_ia64-defconfig_ia64 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/ia64-linux/bin/ia64-linux- defconfig # make -s -j 8 ARCH=ia64 O=/kisskb/build/powerpc-fixes_ia64-defconfig_ia64 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/ia64-linux/bin/ia64-linux- <stdin>:1511:2: warning: #warning syscall clone3 not implemented [-Wcpp] /kisskb/src/kernel/printk/printk.c: In function 'devkmsg_sysctl_set_loglvl': /kisskb/src/kernel/printk/printk.c:204:16: warning: 'old' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/mm/vmstat.c: In function 'sysctl_vm_numa_stat_handler': /kisskb/src/mm/vmstat.c:90:5: warning: 'oldval' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/mm/hugetlb.c: In function 'alloc_pool_huge_page': /kisskb/src/mm/hugetlb.c:1377:5: warning: 'page' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/ext4/extents.c: In function 'ext4_convert_unwritten_io_end_vec': /kisskb/src/fs/ext4/extents.c:5054:23: warning: 'ret' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/nfs/read.c: In function 'nfs_read_completion': /kisskb/src/fs/nfs/read.c:196:5: warning: value computed is not used [-Wunused-value] /kisskb/src/fs/nfs/read.c: In function 'nfs_readpage': /kisskb/src/fs/nfs/read.c:352:2: warning: value computed is not used [-Wunused-value] /kisskb/src/fs/nfsd/nfs4xdr.c: In function 'nfsd4_encode_components_esc': /kisskb/src/fs/nfsd/nfs4xdr.c:2076:9: warning: 'str' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/proc/inode.c: In function 'proc_reg_open': /kisskb/src/include/linux/list.h:65:12: warning: 'pdeo' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/proc/inode.c:338:21: note: 'pdeo' was declared here /kisskb/src/fs/udf/unicode.c: In function 'udf_name_conv_char': /kisskb/src/fs/udf/unicode.c:132:8: warning: 'c' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/include/linux/of_mdio.h:58:13: warning: 'of_mdiobus_child_is_phy' defined but not used [-Wunused-function] /kisskb/src/drivers/usb/core/devio.c: In function 'async_completed': /kisskb/src/drivers/usb/core/devio.c:625:23: warning: 'errno' may be used uninitialized in this function [-Wuninitialized] No errors detected in 21945 functions. Completed OK # rm -rf /kisskb/build/powerpc-fixes_ia64-defconfig_ia64 # Build took: 0:03:01.070349

© Michael Ellerman 2006-2018.