kernel/linux.git/samples, branch linux-4.20.y

samples/bpf: workaround clang asm goto compilation errors

2019-02-27T09:09:49+00:00

[ Upstream commit 6bf3bbe1f4d4cf405e3c2bf07bbdff56d3223ec8 ] x86 compilation has required asm goto support since 4.17. Since clang does not support asm goto, at 4.17, Commit b1ae32dbab50 ("x86/cpufeature: Guard asm_volatile_goto usage for BPF compilation") worked around the issue by permitting an alternative implementation without asm goto for clang. At 5.0, more asm goto usages appeared. [yhs@148 x86]$ egrep -r asm_volatile_goto include/asm/cpufeature.h: asm_volatile_goto("1: jmp 6f\n" include/asm/jump_label.h: asm_volatile_goto("1:" include/asm/jump_label.h: asm_volatile_goto("1:" include/asm/rmwcc.h: asm_volatile_goto (fullop "; j" #cc " %l[cc_label]" \ include/asm/uaccess.h: asm_volatile_goto("\n" \ include/asm/uaccess.h: asm_volatile_goto("\n" \ [yhs@148 x86]$ Compiling samples/bpf directories, most bpf programs failed compilation with error messages like: In file included from /home/yhs/work/bpf-next/samples/bpf/xdp_sample_pkts_kern.c:2: In file included from /home/yhs/work/bpf-next/include/linux/ptrace.h:6: In file included from /home/yhs/work/bpf-next/include/linux/sched.h:15: In file included from /home/yhs/work/bpf-next/include/linux/sem.h:5: In file included from /home/yhs/work/bpf-next/include/uapi/linux/sem.h:5: In file included from /home/yhs/work/bpf-next/include/linux/ipc.h:9: In file included from /home/yhs/work/bpf-next/include/linux/refcount.h:72: /home/yhs/work/bpf-next/arch/x86/include/asm/refcount.h:70:9: error: 'asm goto' constructs are not supported yet return GEN_BINARY_SUFFIXED_RMWcc(LOCK_PREFIX "subl", ^ /home/yhs/work/bpf-next/arch/x86/include/asm/rmwcc.h:67:2: note: expanded from macro 'GEN_BINARY_SUFFIXED_RMWcc' __GEN_RMWcc(op " %[val], %[var]\n\t" suffix, var, cc, \ ^ /home/yhs/work/bpf-next/arch/x86/include/asm/rmwcc.h:21:2: note: expanded from macro '__GEN_RMWcc' asm_volatile_goto (fullop "; j" #cc " %l[cc_label]" \ ^ /home/yhs/work/bpf-next/include/linux/compiler_types.h:188:37: note: expanded from macro 'asm_volatile_goto' #define asm_volatile_goto(x...) asm goto(x) Most implementation does not even provide an alternative implementation. And it is also not practical to make changes for each call site. This patch workarounded the asm goto issue by redefining the macro like below: #define asm_volatile_goto(x...) asm volatile("invalid use of asm_volatile_goto") If asm_volatile_goto is not used by bpf programs, which is typically the case, nothing bad will happen. If asm_volatile_goto is used by bpf programs, which is incorrect, the compiler will issue an error since "invalid use of asm_volatile_goto" is not valid assembly codes. With this patch, all bpf programs under samples/bpf can pass compilation. Note that bpf programs under tools/testing/selftests/bpf/ compiled fine as they do not access kernel internal headers. Fixes: e769742d3584 ("Revert "x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs"") Fixes: 18fe58229d80 ("x86, asm: change the GEN_*_RMWcc() macros to not quote the condition") Acked-by: Alexei Starovoitov Signed-off-by: Yonghong Song Signed-off-by: Daniel Borkmann Signed-off-by: Sasha Levin

samples: mei: use /dev/mei0 instead of /dev/mei

2019-02-15T07:11:04+00:00

commit c4a46acf1db3ce547d290c29e55b3476c78dd76c upstream. The device was moved from misc device to character devices to support multiple mei devices. Cc: #v4.9+ Signed-off-by: Tomas Winkler Signed-off-by: Greg Kroah-Hartman

livepatch: check kzalloc return values

2019-02-12T19:02:22+00:00

[ Upstream commit 5f30b2e823484ce6a79f2b59901b6351c15effa6 ] kzalloc() return should always be checked - notably in example code where this may be seen as reference. On failure of allocation in livepatch_fix1_dummy_alloc() respectively dummy_alloc() previous allocation is freed (thanks to Petr Mladek for catching this) and NULL returned. Signed-off-by: Nicholas Mc Guire Fixes: 439e7271dc2b ("livepatch: introduce shadow variable API") Acked-by: Joe Lawrence Reviewed-by: Petr Mladek Acked-by: Miroslav Benes Signed-off-by: Jiri Kosina Signed-off-by: Sasha Levin

samples: bpf: fix: error handling regarding kprobe_events

2019-01-26T08:20:42+00:00

[ Upstream commit 5a863813216ce79e16a8c1503b2543c528b778b6 ] Currently, kprobe_events failure won't be handled properly. Due to calling system() indirectly to write to kprobe_events, it can't be identified whether an error is derived from kprobe or system. // buf = "echo '%c:%s %s' >> /s/k/d/t/kprobe_events" err = system(buf); if (err < 0) { printf("failed to create kprobe .."); return -1; } For example, running ./tracex7 sample in ext4 partition, "echo p:open_ctree open_ctree >> /s/k/d/t/kprobe_events" gets 256 error code system() failure. => The error comes from kprobe, but it's not handled correctly. According to man of system(3), it's return value just passes the termination status of the child shell rather than treating the error as -1. (don't care success) Which means, currently it's not working as desired. (According to the upper code snippet) ex) running ./tracex7 with ext4 env. # Current Output sh: echo: I/O error failed to open event open_ctree # Desired Output failed to create kprobe 'open_ctree' error 'No such file or directory' The problem is, error can't be verified whether from child ps or system. But using write() directly can verify the command failure, and it will treat all error as -1. So I suggest using write() directly to 'kprobe_events' rather than calling system(). Signed-off-by: Daniel T. Lee Signed-off-by: Daniel Borkmann Signed-off-by: Sasha Levin

Merge tag 'vfio-v4.20-rc1.v2' of git://github.com/awilliam/linux-vfio

2018-10-31T18:01:38+00:00

Pull VFIO updates from Alex Williamson: - EDID interfaces for vfio devices supporting display extensions (Gerd Hoffmann) - Generically select Type-1 IOMMU model support on ARM/ARM64 (Geert Uytterhoeven) - Quirk for VFs reporting INTx pin (Alex Williamson) - Fix error path memory leak in MSI support (Li Qiang) * tag 'vfio-v4.20-rc1.v2' of git://github.com/awilliam/linux-vfio: vfio: add edid support to mbochs sample driver vfio: add edid api for display (vgpu) devices. drivers/vfio: Allow type-1 IOMMU instantiation with all ARM/ARM64 IOMMUs vfio/pci: Mask buggy SR-IOV VF INTx support vfio/pci: Fix potential memory leak in vfio_msi_cap_len

Merge tag 'char-misc-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

2018-10-26T16:11:43+00:00

Pull char/misc driver updates from Greg KH: "Here is the big set of char/misc patches for 4.20-rc1. Loads of things here, we have new code in all of these driver subsystems: - fpga - stm - extcon - nvmem - eeprom - hyper-v - gsmi - coresight - thunderbolt - vmw_balloon - goldfish - soundwire along with lots of fixes and minor changes to other small drivers. All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (245 commits) Documentation/security-bugs: Clarify treatment of embargoed information lib: Fix ia64 bootloader linkage MAINTAINERS: Clarify UIO vs UIOVEC maintainer docs/uio: fix a grammar nitpick docs: fpga: document programming fpgas using regions fpga: add devm_fpga_region_create fpga: bridge: add devm_fpga_bridge_create fpga: mgr: add devm_fpga_mgr_create hv_balloon: Replace spin_is_locked() with lockdep sgi-xp: Replace spin_is_locked() with lockdep eeprom: New ee1004 driver for DDR4 memory eeprom: at25: remove unneeded 'at25_remove' w1: IAD Register is yet readable trough iad sys file. Fix snprintf (%u for unsigned, count for max size). misc: mic: scif: remove set but not used variables 'src_dma_addr, dst_dma_addr' misc: mic: fix a DMA pool free failure platform: goldfish: pipe: Add a blank line to separate varibles and code platform: goldfish: pipe: Remove redundant casting platform: goldfish: pipe: Call misc_deregister if init fails platform: goldfish: pipe: Move the file-scope goldfish_pipe_dev variable into the driver state platform: goldfish: pipe: Move the file-scope goldfish_pipe_miscdev variable into the driver state ...

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2018-10-13T04:38:46+00:00

Conflicts were easy to resolve using immediate context mostly, except the cls_u32.c one where I simply too the entire HEAD chunk. Signed-off-by: David S. Miller

vfio: add edid support to mbochs sample driver

2018-10-11T16:22:36+00:00

Signed-off-by: Gerd Hoffmann Signed-off-by: Alex Williamson

samples: disable CONFIG_SAMPLES for UML

2018-10-10T17:15:46+00:00

Some samples require headers installation, so commit 3fca1700c4c3 ("kbuild: make samples really depend on headers_install") added such dependency in the top Makefile. However, UML fails to build with CONFIG_SAMPLES=y because UML does not support headers_install. Fixes: 3fca1700c4c3 ("kbuild: make samples really depend on headers_install") Reported-by: Kees Cook Cc: David Howells Signed-off-by: Masahiro Yamada

bpf, tracex3_user: erase "ARRAY_SIZE" redefined

2018-10-04T14:31:57+00:00

There is a warning when compiling bpf sample programs in sample/bpf: make -C /home/foo/bpf/samples/bpf/../../tools/lib/bpf/ RM='rm -rf' LDFLAGS= srctree=/home/foo/bpf/samples/bpf/../../ O= HOSTCC /home/foo/bpf/samples/bpf/tracex3_user.o /home/foo/bpf/samples/bpf/tracex3_user.c:20:0: warning: "ARRAY_SIZE" redefined #define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x))) In file included from /home/foo/bpf/samples/bpf/tracex3_user.c:18:0: ./tools/testing/selftests/bpf/bpf_util.h:48:0: note: this is the location of the previous definition # define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) Signed-off-by: Bo YU Signed-off-by: Daniel Borkmann