forked from TencentOS/TencentOS-kernel
9 Commits
| Author | SHA1 | Message | Date |
|---|---|---|---|
Tony Ambardar
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6e5ae41b49 |
bpf: Prevent .BTF section elimination
commit 65c204398928f9c79f1a29912b410439f7052635 upstream.
Systems with memory or disk constraints often reduce the kernel footprint
by configuring LD_DEAD_CODE_DATA_ELIMINATION. However, this can result in
removal of any BTF information.
Use the KEEP() macro to preserve the BTF data as done with other important
sections, while still allowing for smaller kernels.
Fixes: 90ceddcb4950 ("bpf: Support llvm-objcopy for vmlinux BTF")
Signed-off-by: Tony Ambardar <Tony.Ambardar@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/a635b5d3e2da044e7b51ec1315e8910fbce0083f.1600417359.git.Tony.Ambardar@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Vasily Gorbik
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ae3536fbc0 |
mm/gup: fix gup_fast with dynamic page table folding
commit d3f7b1bb204099f2f7306318896223e8599bb6a2 upstream.
Currently to make sure that every page table entry is read just once
gup_fast walks perform READ_ONCE and pass pXd value down to the next
gup_pXd_range function by value e.g.:
static int gup_pud_range(p4d_t p4d, unsigned long addr, unsigned long end,
unsigned int flags, struct page **pages, int *nr)
...
pudp = pud_offset(&p4d, addr);
This function passes a reference on that local value copy to pXd_offset,
and might get the very same pointer in return. This happens when the
level is folded (on most arches), and that pointer should not be
iterated.
On s390 due to the fact that each task might have different 5,4 or
3-level address translation and hence different levels folded the logic
is more complex and non-iteratable pointer to a local copy leads to
severe problems.
Here is an example of what happens with gup_fast on s390, for a task
with 3-level paging, crossing a 2 GB pud boundary:
// addr = 0x1007ffff000, end = 0x10080001000
static int gup_pud_range(p4d_t p4d, unsigned long addr, unsigned long end,
unsigned int flags, struct page **pages, int *nr)
{
unsigned long next;
pud_t *pudp;
// pud_offset returns &p4d itself (a pointer to a value on stack)
pudp = pud_offset(&p4d, addr);
do {
// on second iteratation reading "random" stack value
pud_t pud = READ_ONCE(*pudp);
// next = 0x10080000000, due to PUD_SIZE/MASK != PGDIR_SIZE/MASK on s390
next = pud_addr_end(addr, end);
...
} while (pudp++, addr = next, addr != end); // pudp++ iterating over stack
return 1;
}
This happens since s390 moved to common gup code with commit
d1874a0c2805 ("s390/mm: make the pxd_offset functions more robust") and
commit 1a42010cdc26 ("s390/mm: convert to the generic
get_user_pages_fast code").
s390 tried to mimic static level folding by changing pXd_offset
primitives to always calculate top level page table offset in pgd_offset
and just return the value passed when pXd_offset has to act as folded.
What is crucial for gup_fast and what has been overlooked is that
PxD_SIZE/MASK and thus pXd_addr_end should also change correspondingly.
And the latter is not possible with dynamic folding.
To fix the issue in addition to pXd values pass original pXdp pointers
down to gup_pXd_range functions. And introduce pXd_offset_lockless
helpers, which take an additional pXd entry value parameter. This has
already been discussed in
https://lkml.kernel.org/r/20190418100218.0a4afd51@mschwideX1
Fixes: 1a42010cdc26 ("s390/mm: convert to the generic get_user_pages_fast code")
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Claudio Imbrenda <imbrenda@linux.ibm.com>
Cc: <stable@vger.kernel.org> [5.2+]
Link: https://lkml.kernel.org/r/patch.git-943f1e5dcff2.your-ad-here.call-01599856292-ext-8676@work.hours
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Romain Naour
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f4c84bff5c |
include/asm-generic/vmlinux.lds.h: align ro_after_init
commit 7f897acbe5d57995438c831670b7c400e9c0dc00 upstream. Since the patch [1], building the kernel using a toolchain built with binutils 2.33.1 prevents booting a sh4 system under Qemu. Apply the patch provided by Alan Modra [2] that fix alignment of rodata. [1] https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=ebd2263ba9a9124d93bbc0ece63d7e0fae89b40e [2] https://www.sourceware.org/ml/binutils/2019-12/msg00112.html Signed-off-by: Romain Naour <romain.naour@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Alan Modra <amodra@gmail.com> Cc: Bin Meng <bin.meng@windriver.com> Cc: Chen Zhou <chenzhou10@huawei.com> Cc: Geert Uytterhoeven <geert+renesas@glider.be> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Krzysztof Kozlowski <krzk@kernel.org> Cc: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> Cc: Rich Felker <dalias@libc.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Arnd Bergmann <arnd@arndb.de> Cc: <stable@vger.kernel.org> Link: https://marc.info/?l=linux-sh&m=158429470221261 Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
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Joerg Roedel
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6b304f2857 |
x86, vmlinux.lds: Page-align end of ..page_aligned sections
commit de2b41be8fcccb2f5b6c480d35df590476344201 upstream. On x86-32 the idt_table with 256 entries needs only 2048 bytes. It is page-aligned, but the end of the .bss..page_aligned section is not guaranteed to be page-aligned. As a result, objects from other .bss sections may end up on the same 4k page as the idt_table, and will accidentially get mapped read-only during boot, causing unexpected page-faults when the kernel writes to them. This could be worked around by making the objects in the page aligned sections page sized, but that's wrong. Explicit sections which store only page aligned objects have an implicit guarantee that the object is alone in the page in which it is placed. That works for all objects except the last one. That's inconsistent. Enforcing page sized objects for these sections would wreckage memory sanitizers, because the object becomes artificially larger than it should be and out of bound access becomes legit. Align the end of the .bss..page_aligned and .data..page_aligned section on page-size so all objects places in these sections are guaranteed to have their own page. [ tglx: Amended changelog ] Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20200721093448.10417-1-joro@8bytes.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
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Will Deacon
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9bd5ac4ea6 |
asm-generic/mmiowb: Allow mmiowb_set_pending() when preemptible()
[ Upstream commit bd024e82e4cd95c7f1a475a55f99871936c2b2db ] Although mmiowb() is concerned only with serialising MMIO writes occuring in contexts where a spinlock is held, the call to mmiowb_set_pending() from the MMIO write accessors can occur in preemptible contexts, such as during driver probe() functions where ordering between CPUs is not usually a concern, assuming that the task migration path provides the necessary ordering guarantees. Unfortunately, the default implementation of mmiowb_set_pending() is not preempt-safe, as it makes use of a a per-cpu variable to track its internal state. This has been reported to generate the following splat on riscv: | BUG: using smp_processor_id() in preemptible [00000000] code: swapper/0/1 | caller is regmap_mmio_write32le+0x1c/0x46 | CPU: 3 PID: 1 Comm: swapper/0 Not tainted 5.8.0-rc3-hfu+ #1 | Call Trace: | walk_stackframe+0x0/0x7a | dump_stack+0x6e/0x88 | regmap_mmio_write32le+0x18/0x46 | check_preemption_disabled+0xa4/0xaa | regmap_mmio_write32le+0x18/0x46 | regmap_mmio_write+0x26/0x44 | regmap_write+0x28/0x48 | sifive_gpio_probe+0xc0/0x1da Although it's possible to fix the driver in this case, other splats have been seen from other drivers, including the infamous 8250 UART, and so it's better to address this problem in the mmiowb core itself. Fix mmiowb_set_pending() by using the raw_cpu_ptr() to get at the mmiowb state and then only updating the 'mmiowb_pending' field if we are not preemptible (i.e. we have a non-zero nesting count). Cc: Arnd Bergmann <arnd@arndb.de> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Guo Ren <guoren@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Reported-by: Palmer Dabbelt <palmer@dabbelt.com> Reported-by: Emil Renner Berthing <kernel@esmil.dk> Tested-by: Emil Renner Berthing <kernel@esmil.dk> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com> Link: https://lore.kernel.org/r/20200716112816.7356-1-will@kernel.org Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> |
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Fangrui Song
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66aed5f2e4 |
bpf: Support llvm-objcopy for vmlinux BTF
commit 90ceddcb495008ac8ba7a3dce297841efcd7d584 upstream.
Simplify gen_btf logic to make it work with llvm-objcopy. The existing
'file format' and 'architecture' parsing logic is brittle and does not
work with llvm-objcopy/llvm-objdump.
'file format' output of llvm-objdump>=11 will match GNU objdump, but
'architecture' (bfdarch) may not.
.BTF in .tmp_vmlinux.btf is non-SHF_ALLOC. Add the SHF_ALLOC flag
because it is part of vmlinux image used for introspection. C code
can reference the section via linker script defined __start_BTF and
__stop_BTF. This fixes a small problem that previous .BTF had the
SHF_WRITE flag (objcopy -I binary -O elf* synthesized .data).
Additionally, `objcopy -I binary` synthesized symbols
_binary__btf_vmlinux_bin_start and _binary__btf_vmlinux_bin_stop (not
used elsewhere) are replaced with more commonplace __start_BTF and
__stop_BTF.
Add 2>/dev/null because GNU objcopy (but not llvm-objcopy) warns
"empty loadable segment detected at vaddr=0xffffffff81000000, is this intentional?"
We use a dd command to change the e_type field in the ELF header from
ET_EXEC to ET_REL so that lld will accept .btf.vmlinux.bin.o. Accepting
ET_EXEC as an input file is an extremely rare GNU ld feature that lld
does not intend to support, because this is error-prone.
The output section description .BTF in include/asm-generic/vmlinux.lds.h
avoids potential subtle orphan section placement issues and suppresses
--orphan-handling=warn warnings.
Fixes: df786c9b9476 ("bpf: Force .BTF section start to zero when dumping from vmlinux")
Fixes: cb0cc635c7a9 ("powerpc: Include .BTF section")
Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Fangrui Song <maskray@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Stanislav Fomichev <sdf@google.com>
Tested-by: Andrii Nakryiko <andriin@fb.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Link: https://github.com/ClangBuiltLinux/linux/issues/871
Link: https://lore.kernel.org/bpf/20200318222746.173648-1-maskray@google.com
Signed-off-by: Maria Teguiani <teguiani@google.com>
Tested-by: Matthias Maennich <maennich@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Arnd Bergmann
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30bf2ad233 |
include/asm-generic/topology.h: guard cpumask_of_node() macro argument
[ 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 <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Link: http://lkml.kernel.org/r/20200527134623.930247-1-arnd@arndb.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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Tianyu Lan
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8d8ee263eb |
x86/Hyper-V: Report crash data in die() when panic_on_oops is set
commit f3a99e761efa616028b255b4de58e9b5b87c5545 upstream.
When oops happens with panic_on_oops unset, the oops
thread is killed by die() and system continues to run.
In such case, guest should not report crash register
data to host since system still runs. Check panic_on_oops
and return directly in hyperv_report_panic() when the function
is called in the die() and panic_on_oops is unset. Fix it.
Fixes: 7ed4325a44ea ("Drivers: hv: vmbus: Make panic reporting to be more useful")
Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20200406155331.2105-7-Tianyu.Lan@microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Kaixu Xia
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590eaf1fec |
Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.
Signed-off-by: Kaixu Xia <kaixuxia@tencent.com> |