kernel/linux.git/include/asm-generic, branch v4.4.239

asm-prototypes: Clear any CPP defines before declaring the functions

2020-06-03T06:12:15+00:00

commit c7858bf16c0b2cc62f475f31e6df28c3a68da1d6 upstream. The asm-prototypes.h file is used to provide dummy function declarations for genksyms, when processing asm files with EXPORT_SYMBOL. Make sure that any architecture defines get out of our way. x86 currently has an issue with memcpy on 64bit with CONFIG_KMEMCHECK=y and with memset/__memset on 32bit: $ cat init/test.c #include $ make -s init/test.o In file included from ./arch/x86/include/asm/string.h:4:0, from ./include/linux/string.h:18, from ./include/linux/bitmap.h:8, from ./include/linux/cpumask.h:11, from ./arch/x86/include/asm/cpumask.h:4, from ./arch/x86/include/asm/msr.h:10, from ./arch/x86/include/asm/processor.h:20, from ./arch/x86/include/asm/cpufeature.h:4, from ./arch/x86/include/asm/thread_info.h:52, from ./include/linux/thread_info.h:25, from ./arch/x86/include/asm/preempt.h:6, from ./include/linux/preempt.h:59, from ./include/linux/spinlock.h:50, from ./include/linux/seqlock.h:35, from ./include/linux/time.h:5, from ./include/uapi/linux/timex.h:56, from ./include/linux/timex.h:56, from ./include/linux/sched.h:19, from ./include/linux/uaccess.h:4, from ./arch/x86/include/asm/asm-prototypes.h:2, from init/test.c:1: ./arch/x86/include/asm/string_64.h:52:47: error: expected declaration specifiers or ‘...’ before ‘(’ token #define memcpy(dst, src, len) __inline_memcpy((dst), (src), (len)) ./include/asm-generic/asm-prototypes.h:6:14: note: in expansion of macro ‘memcpy’ extern void *memcpy(void *, const void *, __kernel_size_t); ^ ... During real build, this manifests itself by genksyms segfaulting. Fixes: 334bb7738764 ("x86/kbuild: enable modversions for symbols exported from asm") Reported-and-tested-by: Borislav Petkov Cc: Adam Borowski Signed-off-by: Michal Marek Cc: Guenter Roeck Signed-off-by: Greg Kroah-Hartman

include/asm-generic/topology.h: guard cpumask_of_node() macro argument

2020-06-03T06:12:12+00:00

[ Upstream commit 4377748c7b5187c3342a60fa2ceb60c8a57a8488 ] drivers/hwmon/amd_energy.c:195:15: error: invalid operands to binary expression ('void' and 'int') (channel - data->nr_cpus)); ~~~~~~~~~^~~~~~~~~~~~~~~~~ include/asm-generic/topology.h:51:42: note: expanded from macro 'cpumask_of_node' #define cpumask_of_node(node) ((void)node, cpu_online_mask) ^~~~ include/linux/cpumask.h:618:72: note: expanded from macro 'cpumask_first_and' #define cpumask_first_and(src1p, src2p) cpumask_next_and(-1, (src1p), (src2p)) ^~~~~ Fixes: f0b848ce6fe9 ("cpumask: Introduce cpumask_of_{node,pcibus} to replace {node,pcibus}_to_cpumask") Fixes: 8abee9566b7e ("hwmon: Add amd_energy driver to report energy counters") Signed-off-by: Arnd Bergmann Signed-off-by: Andrew Morton Acked-by: Guenter Roeck Link: http://lkml.kernel.org/r/20200527134623.930247-1-arnd@arndb.de Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

sched/preempt: Fix preempt_count manipulations

2020-05-10T08:26:21+00:00

commit 2e636d5e66c35dfcbaf617aa8fa963f6847478fe upstream. Vikram reported that his ARM64 compiler managed to 'optimize' away the preempt_count manipulations in code like: preempt_enable_no_resched(); put_user(); preempt_disable(); Irrespective of that fact that that is horrible code that should be fixed for many reasons, it does highlight a deficiency in the generic preempt_count manipulators. As it is never right to combine/elide preempt_count manipulations like this. Therefore sprinkle some volatile in the two generic accessors to ensure the compiler is aware of the fact that the preempt_count is observed outside of the regular program-order view and thus cannot be optimized away like this. x86; the only arch not using the generic code is not affected as we do all this in asm in order to use the segment base per-cpu stuff. Reported-by: Vikram Mulukutla Tested-by: Vikram Mulukutla Signed-off-by: Peter Zijlstra (Intel) Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Fixes: a787870924db ("sched, arch: Create asm/preempt.h") Link: http://lkml.kernel.org/r/20160516131751.GH3205@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

rtc: cmos: ignore bogus century byte

2020-01-29T09:21:39+00:00

[ Upstream commit 2a4daadd4d3e507138f8937926e6a4df49c6bfdc ] Older versions of Libreboot and Coreboot had an invalid value (`3' in my case) in the century byte affecting the GM45 in the Thinkpad X200. Not everybody's updated their firmwares, and Linux <= 4.2 was able to read the RTC without problems, so workaround this by ignoring invalid values. Fixes: 3c217e51d8a272b9 ("rtc: cmos: century support") Cc: Alexandre Belloni Cc: Alessandro Zummo Cc: Sylvain Chouleur Cc: Patrick McDermott Cc: linux-rtc@vger.kernel.org Signed-off-by: Eric Wong Signed-off-by: Alexandre Belloni Signed-off-by: Sasha Levin

asm-generic: default BUG_ON(x) to if(x)BUG()

2019-08-25T08:53:04+00:00

commit 3c047057d1206ec0f3b88c7809cacba478067a0c upstream. When CONFIG_BUG is disabled, BUG_ON() will only evaluate the condition, but will not actually stop the current thread. GCC warns about a couple of BUG_ON() users where this actually leads to further undefined behavior: include/linux/ceph/osdmap.h: In function 'ceph_can_shift_osds': include/linux/ceph/osdmap.h:54:1: warning: control reaches end of non-void function fs/ext4/inode.c: In function 'ext4_map_blocks': fs/ext4/inode.c:548:5: warning: 'retval' may be used uninitialized in this function drivers/mfd/db8500-prcmu.c: In function 'prcmu_config_clkout': drivers/mfd/db8500-prcmu.c:762:10: warning: 'div_mask' may be used uninitialized in this function drivers/mfd/db8500-prcmu.c:769:13: warning: 'mask' may be used uninitialized in this function drivers/mfd/db8500-prcmu.c:757:7: warning: 'bits' may be used uninitialized in this function drivers/tty/serial/8250/8250_core.c: In function 'univ8250_release_irq': drivers/tty/serial/8250/8250_core.c:252:18: warning: 'i' may be used uninitialized in this function drivers/tty/serial/8250/8250_core.c:235:19: note: 'i' was declared here There is an obvious conflict of interest here: on the one hand, someone who disables CONFIG_BUG() will want the kernel to be as small as possible and doesn't care about printing error messages to a console that nobody looks at. On the other hand, running into a BUG_ON() condition means that something has gone wrong, and we probably want to also stop doing things that might cause data corruption. This patch picks the second choice, and changes the NOP to BUG(), which normally stops the execution of the current thread in some form (endless loop or a trap). This follows the logic we applied in a4b5d580e078 ("bug: Make BUG() always stop the machine"). For ARM multi_v7_defconfig, the size slightly increases: section CONFIG_BUG=y CONFIG_BUG=n CONFIG_BUG=n+patch .text 8320248 | 8180944 | 8207688 .rodata 3633720 | 3567144 | 3570648 __bug_table 32508 | --- | --- __modver 692 | 1584 | 2176 .init.text 558132 | 548300 | 550088 .exit.text 12380 | 12256 | 12380 .data 1016672 | 1016064 | 1016128 Total 14622556 | 14374510 | 14407326 So instead of saving 1.70% of the total image size, we only save 1.48% by turning off CONFIG_BUG, but in return we can ensure that we don't run into cases of uninitialized variable or return code uses when something bad happens. Aside from that, we significantly reduce the number of warnings in randconfig builds, which makes it easier to fix the warnings about other problems. Signed-off-by: Arnd Bergmann Signed-off-by: Greg Kroah-Hartman

asm-generic: fix -Wtype-limits compiler warnings

2019-08-25T08:53:01+00:00

[ Upstream commit cbedfe11347fe418621bd188d58a206beb676218 ] Commit d66acc39c7ce ("bitops: Optimise get_order()") introduced a compilation warning because "rx_frag_size" is an "ushort" while PAGE_SHIFT here is 16. The commit changed the get_order() to be a multi-line macro where compilers insist to check all statements in the macro even when __builtin_constant_p(rx_frag_size) will return false as "rx_frag_size" is a module parameter. In file included from ./arch/powerpc/include/asm/page_64.h:107, from ./arch/powerpc/include/asm/page.h:242, from ./arch/powerpc/include/asm/mmu.h:132, from ./arch/powerpc/include/asm/lppaca.h:47, from ./arch/powerpc/include/asm/paca.h:17, from ./arch/powerpc/include/asm/current.h:13, from ./include/linux/thread_info.h:21, from ./arch/powerpc/include/asm/processor.h:39, from ./include/linux/prefetch.h:15, from drivers/net/ethernet/emulex/benet/be_main.c:14: drivers/net/ethernet/emulex/benet/be_main.c: In function 'be_rx_cqs_create': ./include/asm-generic/getorder.h:54:9: warning: comparison is always true due to limited range of data type [-Wtype-limits] (((n) < (1UL << PAGE_SHIFT)) ? 0 : \ ^ drivers/net/ethernet/emulex/benet/be_main.c:3138:33: note: in expansion of macro 'get_order' adapter->big_page_size = (1 << get_order(rx_frag_size)) * PAGE_SIZE; ^~~~~~~~~ Fix it by moving all of this multi-line macro into a proper function, and killing __get_order() off. [akpm@linux-foundation.org: remove __get_order() altogether] [cai@lca.pw: v2] Link: http://lkml.kernel.org/r/1564000166-31428-1-git-send-email-cai@lca.pw Link: http://lkml.kernel.org/r/1563914986-26502-1-git-send-email-cai@lca.pw Fixes: d66acc39c7ce ("bitops: Optimise get_order()") Signed-off-by: Qian Cai Reviewed-by: Nathan Chancellor Cc: David S. Miller Cc: Arnd Bergmann Cc: David Howells Cc: Jakub Jelinek Cc: Nick Desaulniers Cc: Bill Wendling Cc: James Y Knight Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

bug.h: work around GCC PR82365 in BUG()

2019-07-10T07:56:42+00:00

[ Upstream commit 173a3efd3edb2ef6ef07471397c5f542a360e9c1 ] Looking at functions with large stack frames across all architectures led me discovering that BUG() suffers from the same problem as fortify_panic(), which I've added a workaround for already. In short, variables that go out of scope by calling a noreturn function or __builtin_unreachable() keep using stack space in functions afterwards. A workaround that was identified is to insert an empty assembler statement just before calling the function that doesn't return. I'm adding a macro "barrier_before_unreachable()" to document this, and insert calls to that in all instances of BUG() that currently suffer from this problem. The files that saw the largest change from this had these frame sizes before, and much less with my patch: fs/ext4/inode.c:82:1: warning: the frame size of 1672 bytes is larger than 800 bytes [-Wframe-larger-than=] fs/ext4/namei.c:434:1: warning: the frame size of 904 bytes is larger than 800 bytes [-Wframe-larger-than=] fs/ext4/super.c:2279:1: warning: the frame size of 1160 bytes is larger than 800 bytes [-Wframe-larger-than=] fs/ext4/xattr.c:146:1: warning: the frame size of 1168 bytes is larger than 800 bytes [-Wframe-larger-than=] fs/f2fs/inode.c:152:1: warning: the frame size of 1424 bytes is larger than 800 bytes [-Wframe-larger-than=] net/netfilter/ipvs/ip_vs_core.c:1195:1: warning: the frame size of 1068 bytes is larger than 800 bytes [-Wframe-larger-than=] net/netfilter/ipvs/ip_vs_core.c:395:1: warning: the frame size of 1084 bytes is larger than 800 bytes [-Wframe-larger-than=] net/netfilter/ipvs/ip_vs_ftp.c:298:1: warning: the frame size of 928 bytes is larger than 800 bytes [-Wframe-larger-than=] net/netfilter/ipvs/ip_vs_ftp.c:418:1: warning: the frame size of 908 bytes is larger than 800 bytes [-Wframe-larger-than=] net/netfilter/ipvs/ip_vs_lblcr.c:718:1: warning: the frame size of 960 bytes is larger than 800 bytes [-Wframe-larger-than=] drivers/net/xen-netback/netback.c:1500:1: warning: the frame size of 1088 bytes is larger than 800 bytes [-Wframe-larger-than=] In case of ARC and CRIS, it turns out that the BUG() implementation actually does return (or at least the compiler thinks it does), resulting in lots of warnings about uninitialized variable use and leaving noreturn functions, such as: block/cfq-iosched.c: In function 'cfq_async_queue_prio': block/cfq-iosched.c:3804:1: error: control reaches end of non-void function [-Werror=return-type] include/linux/dmaengine.h: In function 'dma_maxpq': include/linux/dmaengine.h:1123:1: error: control reaches end of non-void function [-Werror=return-type] This makes them call __builtin_trap() instead, which should normally dump the stack and kill the current process, like some of the other architectures already do. I tried adding barrier_before_unreachable() to panic() and fortify_panic() as well, but that had very little effect, so I'm not submitting that patch. Vineet said: : For ARC, it is double win. : : 1. Fixes 3 -Wreturn-type warnings : : | ../net/core/ethtool.c:311:1: warning: control reaches end of non-void function : [-Wreturn-type] : | ../kernel/sched/core.c:3246:1: warning: control reaches end of non-void function : [-Wreturn-type] : | ../include/linux/sunrpc/svc_xprt.h:180:1: warning: control reaches end of : non-void function [-Wreturn-type] : : 2. bloat-o-meter reports code size improvements as gcc elides the : generated code for stack return. Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82365 Link: http://lkml.kernel.org/r/20171219114112.939391-1-arnd@arndb.de Signed-off-by: Arnd Bergmann Acked-by: Vineet Gupta [arch/arc] Tested-by: Vineet Gupta [arch/arc] Cc: Mikael Starvik Cc: Jesper Nilsson Cc: Tony Luck Cc: Fenghua Yu Cc: Geert Uytterhoeven Cc: "David S. Miller" Cc: Christopher Li Cc: Thomas Gleixner Cc: Peter Zijlstra Cc: Kees Cook Cc: Ingo Molnar Cc: Josh Poimboeuf Cc: Will Deacon Cc: "Steven Rostedt (VMware)" Cc: Mark Rutland Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin [ removed cris changes - gregkh] Signed-off-by: Greg Kroah-Hartman

asm-generic: Fix local variable shadow in __set_fixmap_offset

2019-04-03T04:23:23+00:00

[ Upstream commit 3694bd76781b76c4f8d2ecd85018feeb1609f0e5 ] Currently __set_fixmap_offset is a macro function which has a local variable called 'addr'. If a caller passes a 'phys' parameter which is derived from a variable also called 'addr', the local variable will shadow this, and the compiler will complain about the use of an uninitialized variable. To avoid the issue with namespace clashes, 'addr' is prefixed with a liberal sprinkling of underscores. Turning __set_fixmap_offset into a static inline breaks the build for several architectures. Fixing this properly requires updates to a number of architectures to make them agree on the prototype of __set_fixmap (it could be done as a subsequent patch series). Signed-off-by: Mark Rutland Cc: Arnd Bergmann [catalin.marinas@arm.com: squashed the original function patch and macro fixup] Signed-off-by: Catalin Marinas Signed-off-by: Sasha Levin

ioremap: Update pgtable free interfaces with addr

2018-08-17T18:56:45+00:00

commit 785a19f9d1dd8a4ab2d0633be4656653bd3de1fc upstream. The following kernel panic was observed on ARM64 platform due to a stale TLB entry. 1. ioremap with 4K size, a valid pte page table is set. 2. iounmap it, its pte entry is set to 0. 3. ioremap the same address with 2M size, update its pmd entry with a new value. 4. CPU may hit an exception because the old pmd entry is still in TLB, which leads to a kernel panic. Commit b6bdb7517c3d ("mm/vmalloc: add interfaces to free unmapped page table") has addressed this panic by falling to pte mappings in the above case on ARM64. To support pmd mappings in all cases, TLB purge needs to be performed in this case on ARM64. Add a new arg, 'addr', to pud_free_pmd_page() and pmd_free_pte_page() so that TLB purge can be added later in seprate patches. [toshi.kani@hpe.com: merge changes, rewrite patch description] Fixes: 28ee90fe6048 ("x86/mm: implement free pmd/pte page interfaces") Signed-off-by: Chintan Pandya Signed-off-by: Toshi Kani Signed-off-by: Thomas Gleixner Cc: mhocko@suse.com Cc: akpm@linux-foundation.org Cc: hpa@zytor.com Cc: linux-mm@kvack.org Cc: linux-arm-kernel@lists.infradead.org Cc: Will Deacon Cc: Joerg Roedel Cc: stable@vger.kernel.org Cc: Andrew Morton Cc: Michal Hocko Cc: "H. Peter Anvin" Cc: Link: https://lkml.kernel.org/r/20180627141348.21777-3-toshi.kani@hpe.com Signed-off-by: Greg Kroah-Hartman

x86/speculation/l1tf: Unbreak !__HAVE_ARCH_PFN_MODIFY_ALLOWED architectures

2018-08-15T15:42:11+00:00

commit 6c26fcd2abfe0a56bbd95271fce02df2896cfd24 upstream. pfn_modify_allowed() and arch_has_pfn_modify_check() are outside of the !__ASSEMBLY__ section in include/asm-generic/pgtable.h, which confuses assembler on archs that don't have __HAVE_ARCH_PFN_MODIFY_ALLOWED (e.g. ia64) and breaks build: include/asm-generic/pgtable.h: Assembler messages: include/asm-generic/pgtable.h:538: Error: Unknown opcode `static inline bool pfn_modify_allowed(unsigned long pfn,pgprot_t prot)' include/asm-generic/pgtable.h:540: Error: Unknown opcode `return true' include/asm-generic/pgtable.h:543: Error: Unknown opcode `static inline bool arch_has_pfn_modify_check(void)' include/asm-generic/pgtable.h:545: Error: Unknown opcode `return false' arch/ia64/kernel/entry.S:69: Error: `mov' does not fit into bundle Move those two static inlines into the !__ASSEMBLY__ section so that they don't confuse the asm build pass. Fixes: 42e4089c7890 ("x86/speculation/l1tf: Disallow non privileged high MMIO PROT_NONE mappings") Signed-off-by: Jiri Kosina Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman [groeck: Context changes] Signed-off-by: Guenter Roeck