linux/init, branch v5.7

Merge tag 'x86_urgent_for_v5.7-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2020-05-17T18:08:29Z

Pull x86 fix from Borislav Petkov: "A single fix for early boot crashes of kernels built with gcc10 and stack protector enabled" * tag 'x86_urgent_for_v5.7-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Fix early boot crash on gcc-10, third try

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

2020-05-15T20:10:06Z

Pull networking fixes from David Miller: 1) Fix sk_psock reference count leak on receive, from Xiyu Yang. 2) CONFIG_HNS should be invisible, from Geert Uytterhoeven. 3) Don't allow locking route MTUs in ipv6, RFCs actually forbid this, from Maciej Żenczykowski. 4) ipv4 route redirect backoff wasn't actually enforced, from Paolo Abeni. 5) Fix netprio cgroup v2 leak, from Zefan Li. 6) Fix infinite loop on rmmod in conntrack, from Florian Westphal. 7) Fix tcp SO_RCVLOWAT hangs, from Eric Dumazet. 8) Various bpf probe handling fixes, from Daniel Borkmann. * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (68 commits) selftests: mptcp: pm: rm the right tmp file dpaa2-eth: properly handle buffer size restrictions bpf: Restrict bpf_trace_printk()'s %s usage and add %pks, %pus specifier bpf: Add bpf_probe_read_{user, kernel}_str() to do_refine_retval_range bpf: Restrict bpf_probe_read{, str}() only to archs where they work MAINTAINERS: Mark networking drivers as Maintained. ipmr: Add lockdep expression to ipmr_for_each_table macro ipmr: Fix RCU list debugging warning drivers: net: hamradio: Fix suspicious RCU usage warning in bpqether.c net: phy: broadcom: fix BCM54XX_SHD_SCR3_TRDDAPD value for BCM54810 tcp: fix error recovery in tcp_zerocopy_receive() MAINTAINERS: Add Jakub to networking drivers. MAINTAINERS: another add of Karsten Graul for S390 networking drivers: ipa: fix typos for ipa_smp2p structure doc pppoe: only process PADT targeted at local interfaces selftests/bpf: Enforce returning 0 for fentry/fexit programs bpf: Enforce returning 0 for fentry/fexit progs net: stmmac: fix num_por initialization security: Fix the default value of secid_to_secctx hook libbpf: Fix register naming in PT_REGS s390 macros ...

bpf: Restrict bpf_probe_read{, str}() only to archs where they work

2020-05-15T15:10:36Z

Given the legacy bpf_probe_read{,str}() BPF helpers are broken on archs with overlapping address ranges, we should really take the next step to disable them from BPF use there. To generally fix the situation, we've recently added new helper variants bpf_probe_read_{user,kernel}() and bpf_probe_read_{user,kernel}_str(). For details on them, see 6ae08ae3dea2 ("bpf: Add probe_read_{user, kernel} and probe_read_{user,kernel}_str helpers"). Given bpf_probe_read{,str}() have been around for ~5 years by now, there are plenty of users at least on x86 still relying on them today, so we cannot remove them entirely w/o breaking the BPF tracing ecosystem. However, their use should be restricted to archs with non-overlapping address ranges where they are working in their current form. Therefore, move this behind a CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE and have x86, arm64, arm select it (other archs supporting it can follow-up on it as well). For the remaining archs, they can workaround easily by relying on the feature probe from bpftool which spills out defines that can be used out of BPF C code to implement the drop-in replacement for old/new kernels via: bpftool feature probe macro Suggested-by: Linus Torvalds Signed-off-by: Daniel Borkmann Signed-off-by: Alexei Starovoitov Reviewed-by: Masami Hiramatsu Acked-by: Linus Torvalds Cc: Brendan Gregg Cc: Christoph Hellwig Link: https://lore.kernel.org/bpf/20200515101118.6508-2-daniel@iogearbox.net

x86: Fix early boot crash on gcc-10, third try

2020-05-15T09:48:01Z

... or the odyssey of trying to disable the stack protector for the function which generates the stack canary value. The whole story started with Sergei reporting a boot crash with a kernel built with gcc-10: Kernel panic — not syncing: stack-protector: Kernel stack is corrupted in: start_secondary CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.6.0-rc5—00235—gfffb08b37df9 #139 Hardware name: Gigabyte Technology Co., Ltd. To be filled by O.E.M./H77M—D3H, BIOS F12 11/14/2013 Call Trace: dump_stack panic ? start_secondary __stack_chk_fail start_secondary secondary_startup_64 -—-[ end Kernel panic — not syncing: stack—protector: Kernel stack is corrupted in: start_secondary This happens because gcc-10 tail-call optimizes the last function call in start_secondary() - cpu_startup_entry() - and thus emits a stack canary check which fails because the canary value changes after the boot_init_stack_canary() call. To fix that, the initial attempt was to mark the one function which generates the stack canary with: __attribute__((optimize("-fno-stack-protector"))) ... start_secondary(void *unused) however, using the optimize attribute doesn't work cumulatively as the attribute does not add to but rather replaces previously supplied optimization options - roughly all -fxxx options. The key one among them being -fno-omit-frame-pointer and thus leading to not present frame pointer - frame pointer which the kernel needs. The next attempt to prevent compilers from tail-call optimizing the last function call cpu_startup_entry(), shy of carving out start_secondary() into a separate compilation unit and building it with -fno-stack-protector, was to add an empty asm(""). This current solution was short and sweet, and reportedly, is supported by both compilers but we didn't get very far this time: future (LTO?) optimization passes could potentially eliminate this, which leads us to the third attempt: having an actual memory barrier there which the compiler cannot ignore or move around etc. That should hold for a long time, but hey we said that about the other two solutions too so... Reported-by: Sergei Trofimovich Signed-off-by: Borislav Petkov Tested-by: Kalle Valo Cc: Link: https://lkml.kernel.org/r/20200314164451.346497-1-slyfox@gentoo.org

Merge tag 'trace-v5.7-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

2020-05-12T18:06:26Z

Pull tracing fixes from Steven Rostedt: "Fixes to previous fixes. Unfortunately, the last set of fixes introduced some minor bugs: - The bootconfig apply_xbc() leak fix caused the application to return a positive number on success, when it should have returned zero. - The preempt_irq_delay_thread fix to make the creation code wait for the kthread to finish to prevent it from executing after module unload, can now cause the kthread to exit before it even executes (preventing it to run its tests). - The fix to the bootconfig that fixed the initrd to remove the bootconfig from causing the kernel to panic, now prints a warning that the bootconfig is not found, even when bootconfig is not on the command line" * tag 'trace-v5.7-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: bootconfig: Fix to prevent warning message if no bootconfig option tracing: Wait for preempt irq delay thread to execute tools/bootconfig: Fix apply_xbc() to return zero on success

bootconfig: Fix to prevent warning message if no bootconfig option

2020-05-12T14:42:51Z

Commit de462e5f1071 ("bootconfig: Fix to remove bootconfig data from initrd while boot") causes a cosmetic regression on dmesg, which warns "no bootconfig data" message without bootconfig cmdline option. Fix setup_boot_config() by moving no bootconfig check after commandline option check. Link: http://lkml.kernel.org/r/9b1ba335-071d-c983-89a4-2677b522dcc8@molgen.mpg.de Link: http://lkml.kernel.org/r/158916116468.21787.14558782332170588206.stgit@devnote2 Fixes: de462e5f1071 ("bootconfig: Fix to remove bootconfig data from initrd while boot") Reported-by: Paul Menzel Reviewed-by: Paul Menzel Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)

gcc-10: mark more functions __init to avoid section mismatch warnings

2020-05-10T00:50:03Z

It seems that for whatever reason, gcc-10 ends up not inlining a couple of functions that used to be inlined before. Even if they only have one single callsite - it looks like gcc may have decided that the code was unlikely, and not worth inlining. The code generation difference is harmless, but caused a few new section mismatch errors, since the (now no longer inlined) function wasn't in the __init section, but called other init functions: Section mismatch in reference from the function kexec_free_initrd() to the function .init.text:free_initrd_mem() Section mismatch in reference from the function tpm2_calc_event_log_size() to the function .init.text:early_memremap() Section mismatch in reference from the function tpm2_calc_event_log_size() to the function .init.text:early_memunmap() So add the appropriate __init annotation to make modpost not complain. In both cases there were trivially just a single callsite from another __init function. Signed-off-by: Linus Torvalds

Stop the ad-hoc games with -Wno-maybe-initialized

2020-05-09T20:57:10Z

We have some rather random rules about when we accept the "maybe-initialized" warnings, and when we don't. For example, we consider it unreliable for gcc versions < 4.9, but also if -O3 is enabled, or if optimizing for size. And then various kernel config options disabled it, because they know that they trigger that warning by confusing gcc sufficiently (ie PROFILE_ALL_BRANCHES). And now gcc-10 seems to be introducing a lot of those warnings too, so it falls under the same heading as 4.9 did. At the same time, we have a very straightforward way to _enable_ that warning when wanted: use "W=2" to enable more warnings. So stop playing these ad-hoc games, and just disable that warning by default, with the known and straight-forward "if you want to work on the extra compiler warnings, use W=123". Would it be great to have code that is always so obvious that it never confuses the compiler whether a variable is used initialized or not? Yes, it would. In a perfect world, the compilers would be smarter, and our source code would be simpler. That's currently not the world we live in, though. Signed-off-by: Linus Torvalds

bootconfig: Fix to remove bootconfig data from initrd while boot

2020-05-06T13:04:11Z

If there is a bootconfig data in the tail of initrd/initramfs, initrd image sanity check caused an error while decompression stage as follows. [ 0.883882] Unpacking initramfs... [ 2.696429] Initramfs unpacking failed: invalid magic at start of compressed archive This error will be ignored if CONFIG_BLK_DEV_RAM=n, but CONFIG_BLK_DEV_RAM=y the kernel failed to mount rootfs and causes a panic. To fix this issue, shrink down the initrd_end for removing tailing bootconfig data while boot the kernel. Link: http://lkml.kernel.org/r/158788401014.24243.17424755854115077915.stgit@devnote2 Cc: Borislav Petkov Cc: Kees Cook Cc: Ingo Molnar Cc: Andrew Morton Cc: stable@vger.kernel.org Fixes: 7684b8582c24 ("bootconfig: Load boot config from the tail of initrd") Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)

Merge tag 'kbuild-v5.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

2020-04-11T16:46:12Z

Pull more Kbuild updates from Masahiro Yamada: - raise minimum supported binutils version to 2.23 - remove old CONFIG_AS_* macros that we know binutils >= 2.23 supports - move remaining CONFIG_AS_* tests to Kconfig from Makefile - enable -Wtautological-compare warnings to catch more issues - do not support GCC plugins for GCC <= 4.7 - fix various breakages of 'make xconfig' - include the linker version used for linking the kernel into LINUX_COMPILER, which is used for the banner, and also exposed to /proc/version - link lib-y objects to vmlinux forcibly when CONFIG_MODULES=y, which allows us to remove the lib-ksyms.o workaround, and to solve the last known issue of the LLVM linker - add dummy tools in scripts/dummy-tools/ to enable all compiler tests in Kconfig, which will be useful for distro maintainers - support the single switch, LLVM=1 to use Clang and all LLVM utilities instead of GCC and Binutils. - support LLVM_IAS=1 to enable the integrated assembler, which is still experimental * tag 'kbuild-v5.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (36 commits) kbuild: fix comment about missing include guard detection kbuild: support LLVM=1 to switch the default tools to Clang/LLVM kbuild: replace AS=clang with LLVM_IAS=1 kbuild: add dummy toolchains to enable all cc-option etc. in Kconfig kbuild: link lib-y objects to vmlinux forcibly when CONFIG_MODULES=y MIPS: fw: arc: add __weak to prom_meminit and prom_free_prom_memory kbuild: remove -I$(srctree)/tools/include from scripts/Makefile kbuild: do not pass $(KBUILD_CFLAGS) to scripts/mkcompile_h Documentation/llvm: fix the name of llvm-size kbuild: mkcompile_h: Include $LD version in /proc/version kconfig: qconf: Fix a few alignment issues kconfig: qconf: remove some old bogus TODOs kconfig: qconf: fix support for the split view mode kconfig: qconf: fix the content of the main widget kconfig: qconf: Change title for the item window kconfig: qconf: clean deprecated warnings gcc-plugins: drop support for GCC <= 4.7 kbuild: Enable -Wtautological-compare x86: update AS_* macros to binutils >=2.23, supporting ADX and AVX2 crypto: x86 - clean up poly1305-x86_64-cryptogams.S by 'make clean' ...