- 16 Jan, 2018 1 commit
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Nathan Fontenot authored
Look up the device node for the associativity array property instead of having it passed in as a parameter. This changes precedes an update in which the calling routines for of_get_assoc_arrays() will not have the device node pointer to pass in. Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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- 03 Jan, 2018 1 commit
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Michael Ellerman authored
Add a test case of the error code reported when we take a SEGV on a mapped but inaccessible area. We broke this recently. Based on a test case from John Sperbeck <jsperbeck@google.com>. Acked-by: John Sperbeck <jsperbeck@google.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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- 22 Dec, 2017 3 commits
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Aneesh Kumar K.V authored
pte_access_premitted get called in get_user_pages_fast path. If we have marked the pte PROT_NONE, we should not allow a read access on the address. With the current implementation we are not checking the READ and only check for WRITE. This is needed on archs like ppc64 that implement PROT_NONE using _PAGE_USER access instead of _PAGE_PRESENT. Also add pte_user check just to make sure we are not accessing kernel mapping. Even though there is code duplication, keeping the low level pte accessors different for different platforms helps in code readability. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Aneesh Kumar K.V authored
pte_access_premitted get called in get_user_pages_fast path. If we have marked the pte PROT_NONE, we should not allow a read access on the address. With the current implementation we are not checking the READ and only check for WRITE. This is needed on archs like ppc64 that implement PROT_NONE using RWX access instead of _PAGE_PRESENT. Also add pte_user check just to make sure we are not accessing kernel mapping. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Aneesh Kumar K.V authored
No functional change in this patch. This update gup_hugepte to use the helper. This will help later when we add memory keys. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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- 20 Dec, 2017 8 commits
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Ram Pai authored
The H_PAGE_F_SECOND,H_PAGE_F_GIX are not in the 64K main-PTE. capture these changes in the dump pte report. Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Ram Pai authored
replace redundant code in __hash_page_4K() and flush_hash_page() with helper functions pte_get_hash_gslot() and pte_set_hidx() Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Ram Pai authored
We need PTE bits 3 ,4, 5, 6 and 57 to support protection-keys, because these are the bits we want to consolidate on across all configuration to support protection keys. Bit 3,4,5 and 6 are currently used on 4K-pte kernels. But bit 9 and 10 are available. Hence we use the two available bits and free up bit 5 and 6. We will still not be able to free up bit 3 and 4. In the absence of any other free bits, we will have to stay satisfied with what we have :-(. This means we will not be able to support 32 protection keys, but only 8. The bit numbers are big-endian as defined in the ISA3.0 This patch does the following change to 4K PTE. H_PAGE_F_SECOND (S) which occupied bit 4 moves to bit 7. H_PAGE_F_GIX (G,I,X) which occupied bit 5, 6 and 7 also moves to bit 8,9, 10 respectively. H_PAGE_HASHPTE (H) which occupied bit 8 moves to bit 4. Before the patch, the 4k PTE format was as follows 0 1 2 3 4 5 6 7 8 9 10....................57.....63 : : : : : : : : : : : : : v v v v v v v v v v v v v ,-,-,-,-,--,--,--,--,-,-,-,-,-,------------------,-,-,-, |x|x|x|B|S |G |I |X |H| | |x|x|................| |x|x|x| '_'_'_'_'__'__'__'__'_'_'_'_'_'________________'_'_'_'_' After the patch, the 4k PTE format is as follows 0 1 2 3 4 5 6 7 8 9 10....................57.....63 : : : : : : : : : : : : : v v v v v v v v v v v v v ,-,-,-,-,--,--,--,--,-,-,-,-,-,------------------,-,-,-, |x|x|x|B|H | | |S |G|I|X|x|x|................| |.|.|.| '_'_'_'_'__'__'__'__'_'_'_'_'_'________________'_'_'_'_' The patch has no code changes; just swizzles around bits. Signed-off-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Ram Pai authored
0xf is considered invalid hidx value. It indicates absence of a backing HPTE. A PTE is initialized to 0xf either a) when it is new it is newly allocated to hold 4k-backing-HPTE or b) Any time it gets demoted to a 4k-backing-HPTE This patch shifts the representation by one-modulo-0xf; i.e hidx 0 is represented as 1, 1 as 2,... , and 0xf as 0. This convention lets us initialize the secondary-part of the PTE to all zeroes. PTEs are anyway zero'd when allocated. We do not have to zero them again; thus saving on the initialization. Signed-off-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Ram Pai authored
Rearrange 64K PTE bits to free up bits 3, 4, 5 and 6 in the 64K backed HPTE pages. This along with the earlier patch will entirely free up the four bits from 64K PTE. The bit numbers are big-endian as defined in the ISA3.0 This patch does the following change to 64K PTE backed by 64K HPTE. H_PAGE_F_SECOND (S) which occupied bit 4 moves to the second part of the pte to bit 60. H_PAGE_F_GIX (G,I,X) which occupied bit 5, 6 and 7 also moves to the second part of the pte to bit 61, 62, 63, 64 respectively since bit 7 is now freed up, we move H_PAGE_BUSY (B) from bit 9 to bit 7. The second part of the PTE will hold (H_PAGE_F_SECOND|H_PAGE_F_GIX) at bit 60,61,62,63. NOTE: None of the bits in the secondary PTE were not used by 64k-HPTE backed PTE. Before the patch, the 64K HPTE backed 64k PTE format was as follows 0 1 2 3 4 5 6 7 8 9 10...........................63 : : : : : : : : : : : : v v v v v v v v v v v v ,-,-,-,-,--,--,--,--,-,-,-,-,-,------------------,-,-,-, |x|x|x| |S |G |I |X |x|B| |x|x|................|x|x|x|x| <- primary pte '_'_'_'_'__'__'__'__'_'_'_'_'_'________________'_'_'_'_' | | | | | | | | | | | | |..................| | | | | <- secondary pte '_'_'_'_'__'__'__'__'_'_'_'_'__________________'_'_'_'_' After the patch, the 64k HPTE backed 64k PTE format is as follows 0 1 2 3 4 5 6 7 8 9 10...........................63 : : : : : : : : : : : : v v v v v v v v v v v v ,-,-,-,-,--,--,--,--,-,-,-,-,-,------------------,-,-,-, |x|x|x| | | | |B |x| | |x|x|................|.|.|.|.| <- primary pte '_'_'_'_'__'__'__'__'_'_'_'_'_'________________'_'_'_'_' | | | | | | | | | | | | |..................|S|G|I|X| <- secondary pte '_'_'_'_'__'__'__'__'_'_'_'_'__________________'_'_'_'_' The above PTE changes is applicable to hugetlbpages aswell. The patch does the following code changes: a) moves the H_PAGE_F_SECOND and H_PAGE_F_GIX to 4k PTE header since it is no more needed b the 64k PTEs. b) abstracts out __real_pte() and __rpte_to_hidx() so the caller need not know the bit location of the slot. c) moves the slot bits to the secondary pte. Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Ram Pai authored
Rearrange 64K PTE bits to free up bits 3, 4, 5 and 6, in the 4K backed HPTE pages.These bits continue to be used for 64K backed HPTE pages in this patch, but will be freed up in the next patch. The bit numbers are big-endian as defined in the ISA3.0 The patch does the following change to the 4k HTPE backed 64K PTE's format. H_PAGE_BUSY moves from bit 3 to bit 9 (B bit in the figure below) V0 which occupied bit 4 is not used anymore. V1 which occupied bit 5 is not used anymore. V2 which occupied bit 6 is not used anymore. V3 which occupied bit 7 is not used anymore. Before the patch, the 4k backed 64k PTE format was as follows 0 1 2 3 4 5 6 7 8 9 10...........................63 : : : : : : : : : : : : v v v v v v v v v v v v ,-,-,-,-,--,--,--,--,-,-,-,-,-,------------------,-,-,-, |x|x|x|B|V0|V1|V2|V3|x| | |x|x|................|x|x|x|x| <- primary pte '_'_'_'_'__'__'__'__'_'_'_'_'_'________________'_'_'_'_' |S|G|I|X|S |G |I |X |S|G|I|X|..................|S|G|I|X| <- secondary pte '_'_'_'_'__'__'__'__'_'_'_'_'__________________'_'_'_'_' After the patch, the 4k backed 64k PTE format is as follows 0 1 2 3 4 5 6 7 8 9 10...........................63 : : : : : : : : : : : : v v v v v v v v v v v v ,-,-,-,-,--,--,--,--,-,-,-,-,-,------------------,-,-,-, |x|x|x| | | | | |x|B| |x|x|................|.|.|.|.| <- primary pte '_'_'_'_'__'__'__'__'_'_'_'_'_'________________'_'_'_'_' |S|G|I|X|S |G |I |X |S|G|I|X|..................|S|G|I|X| <- secondary pte '_'_'_'_'__'__'__'__'_'_'_'_'__________________'_'_'_'_' the four bits S,G,I,X (one quadruplet per 4k HPTE) that cache the hash-bucket slot value, is initialized to 1,1,1,1 indicating -- an invalid slot. If a HPTE gets cached in a 1111 slot(i.e 7th slot of secondary hash bucket), it is released immediately. In other words, even though 1111 is a valid slot value in the hash bucket, we consider it invalid and release the slot and the HPTE. This gives us the opportunity to determine the validity of S,G,I,X bits based on its contents and not on any of the bits V0,V1,V2 or V3 in the primary PTE When we release a HPTE cached in the 1111 slot we also release a legitimate slot in the primary hash bucket and unmap its corresponding HPTE. This is to ensure that we do get a HPTE cached in a slot of the primary hash bucket, the next time we retry. Though treating 1111 slot as invalid, reduces the number of available slots in the hash bucket and may have an effect on the performance, the probabilty of hitting a 1111 slot is extermely low. Compared to the current scheme, the above scheme reduces the number of false hash table updates significantly and has the added advantage of releasing four valuable PTE bits for other purpose. NOTE:even though bits 3, 4, 5, 6, 7 are not used when the 64K PTE is backed by 4k HPTE, they continue to be used if the PTE gets backed by 64k HPTE. The next patch will decouple that aswell, and truely release the bits. This idea was jointly developed by Paul Mackerras, Aneesh, Michael Ellermen and myself. 4K PTE format remains unchanged currently. The patch does the following code changes a) PTE flags are split between 64k and 4k header files. b) __hash_page_4K() is reimplemented to reflect the above logic. Acked-by: Balbir Singh <bsingharora@gmail.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Ram Pai authored
Introduce pte_get_hash_gslot()() which returns the global slot number of the HPTE in the global hash table. This function will come in handy as we work towards re-arranging the PTE bits in the later patches. Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Ram Pai authored
Introduce pte_set_hidx().It sets the (H_PAGE_F_SECOND|H_PAGE_F_GIX) bits at the appropriate location in the PTE of 4K PTE. For 64K PTE, it sets the bits in the second part of the PTE. Though the implementation for the former just needs the slot parameter, it does take some additional parameters to keep the prototype consistent. This function will be handy as we work towards re-arranging the bits in the subsequent patches. Acked-by: Balbir Singh <bsingharora@gmail.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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- 11 Dec, 2017 19 commits
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Simon Guo authored
GCC 7 will take "r2" in clobber list as an error and it will get following build errors for powerpc ptrace selftests even with -fno-pic option: ptrace-tm-vsx.c: In function ‘tm_vsx’: ptrace-tm-vsx.c:42:2: error: PIC register clobbered by ‘r2’ in ‘asm’ asm __volatile__( ^~~ make[1]: *** [ptrace-tm-vsx] Error 1 ptrace-tm-spd-vsx.c: In function ‘tm_spd_vsx’: ptrace-tm-spd-vsx.c:55:2: error: PIC register clobbered by ‘r2’ in ‘asm’ asm __volatile__( ^~~ make[1]: *** [ptrace-tm-spd-vsx] Error 1 ptrace-tm-spr.c: In function ‘tm_spr’: ptrace-tm-spr.c:46:2: error: PIC register clobbered by ‘r2’ in ‘asm’ asm __volatile__( ^~~ Fix the build error by removing "r2" from the clobber list. None of these asm blocks actually clobber r2. Reported-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Tested-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Bryant G. Ly authored
Add a pci_vf_drivers_autoprobe() interface. Setting autoprobe to false on the PF prevents drivers from binding to VFs when they are enabled. Signed-off-by: Bryant G. Ly <bryantly@linux.vnet.ibm.com> Signed-off-by: Juan J. Alvarez <jjalvare@linux.vnet.ibm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Russell Currey <ruscur@russell.cc> Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Bryant G. Ly authored
Add calls for pseries platform to configure/deconfigure SR-IOV. Signed-off-by: Bryant G. Ly <bryantly@linux.vnet.ibm.com> Signed-off-by: Juan J. Alvarez <jjalvare@us.ibm.com> Acked-by: Russell Currey <ruscur@russell.cc> Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Bryant G. Ly authored
SR-IOV can now be enabled for the powernv platform and pseries platform. Therefore move the appropriate calls to machine dependent code instead of relying on definition at compile time. Signed-off-by: Bryant G. Ly <bryantly@linux.vnet.ibm.com> Signed-off-by: Juan J. Alvarez <jjalvare@us.ibm.com> Acked-by: Russell Currey <ruscur@russell.cc> Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Alan Modra authored
powerpc64 gcc can generate code that offsets an address, to access part of an object in memory. If the address is a -mcmodel=medium toc pointer relative address then code like the following is possible. addis r9,r2,var@toc@ha ld r3,var@toc@l(r9) ld r4,(var+8)@toc@l(r9) This works fine so long as var is naturally aligned, *and* r2 is sufficiently aligned. If not, there is a possibility that the offset added to access var+8 wraps over a n*64k+32k boundary. Modules don't have any guarantee that r2 is sufficiently aligned. Moreover, code generated by older compilers generates a .toc section with 2**0 alignment, which can result in relocation failures at module load time even without the wrap problem. Thus, this patch links modules with an aligned .toc section (Makefile and module.lds changes), and forces alignment for out of tree modules or those without a .toc section (module_64.c changes). Signed-off-by: Alan Modra <amodra@gmail.com> [desnesn: updated patch to apply to powerpc-next kernel v4.15 ] Signed-off-by: Desnes A. Nunes do Rosario <desnesn@linux.vnet.ibm.com> [mpe: Fix out-of-tree build, swap -256 for ~0xff, reflow comment] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Nicholas Piggin authored
When an interrupt is returning to a soft-disabled context (which can happen for non-maskable interrupts or synchronous interrupts), it goes through the motions of soft-disabling again, including calling TRACE_DISABLE_INTS (i.e., trace_hardirqs_off()). This is not necessary, because we must already be soft-disabled in the interrupt context, it also may be causing crashes in the irq tracing code to re-enter as an nmi. Replace it with a warning to ensure that soft-interrupts are still disabled. Fixes: 7c0482e3 ("powerpc/irq: Fix another case of lazy IRQ state getting out of sync") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Ivan Mikhaylov authored
Add irq error handlers for cmu, plb, opb, mcue, conf with debug information output in case of problems. Signed-off-by: Ivan Mikhaylov <ivan@de.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Ivan Mikhaylov authored
TVSENSE(temperature and voltage sensors) reset is blocked (clock gated) by the POR default of the TVS sleep config bit. As a consequence, TVSENSE will provide erratic sensor values, which may result in spurious (parity) errors recorded in the CMU FIR and leading to erroneous interrupt requests once the CMU interrupt is unmasked. Purpose of this to set up CMU in working state in any cases even in case of parity errors. Reviewed-by: Alistair Popple <alistair@popple.id.au> Signed-off-by: Ivan Mikhaylov <ivan@de.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Ivan Mikhaylov authored
* clear out any possible plb6 errors * board interrupt handling setup within l2 reg set * fsp2 parity error setup All those points are needed for correct interrupt handling on board level including error handling report. Reviewed-by: Alistair Popple <alistair@popple.id.au> Signed-off-by: Ivan Mikhaylov <ivan@de.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Ivan Mikhaylov authored
Add cmu, plbX, l2, ddr3/4, crcs register definitions. Add mfcmu, mtcmu functions for indirect access to cmu. Add mtl2, mfl2 same for l2 cache core reg set. Signed-off-by: Ivan Mikhaylov <ivan@de.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Nicholas Piggin authored
Match powerpc/64 and include .data.rel* input sections in the .data output section explicitly. This solves the warning: powerpc-linux-gnu-ld: warning: orphan section `.data.rel.ro' from `arch/powerpc/kernel/head_44x.o' being placed in section `.data.rel.ro'. Link: https://lists.01.org/pipermail/kbuild-all/2017-November/040010.htmlReported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Michael Ellerman authored
As far as I can tell CONFIG_CPM is the right symbol to use to conditionally compile the cpm-serial.c code. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Michael Ellerman authored
Only build the OPAL console code in when necessary. This looks like it should use CONFIG_PPC_POWERNV, but because the opal-call.S code is 64-bit only, we must only build it when we're building the boot wrapper 64-bit. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Michael Ellerman authored
The serial code in uartlite.c only matches if we find one of two Xilinx (xlnx) nodes in the device tree, there's no need to build or link the code on other platforms. As far as I can tell CONFIG_XILINX_VIRTEX is the appropriate symbol to use to conditionally compile the code. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Josh Poimboeuf authored
Print the function address associated with the restore_r2() error to make it easier to debug the problem. Also clarify the wording a bit. Before: module_64: patch_foo: Expect noop after relocate, got 3c820000 After: module_64: patch_foo: Expected nop after call, got 7c630034 at netdev_has_upper_dev+0x54/0xb0 [patch_foo] Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> [mpe: Change noop to nop, as that's the name of the instruction] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Josh Poimboeuf authored
When attempting to load a livepatch module, I got the following error: module_64: patch_module: Expect noop after relocate, got 3c820000 The error was triggered by the following code in unregister_netdevice_queue(): 14c: 00 00 00 48 b 14c <unregister_netdevice_queue+0x14c> 14c: R_PPC64_REL24 net_set_todo 150: 00 00 82 3c addis r4,r2,0 GCC didn't insert a nop after the branch to net_set_todo() because it's a sibling call, so it never returns. The nop isn't needed after the branch in that case. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Reviewed-and-tested-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Kamalesh Babulal authored
Livepatch re-uses module loader function apply_relocate_add() to write relocations, instead of managing them by arch-dependent klp_write_module_reloc() function. apply_relocate_add() doesn't understand livepatch symbols (marked with SHN_LIVEPATCH symbol section index) and assumes them to be local symbols by default for R_PPC64_REL24 relocation type. It fails with an error, when trying to calculate offset with local_entry_offset(): module_64: kpatch_meminfo: REL24 -1152921504897399800 out of range! Whereas livepatch symbols are essentially SHN_UNDEF, should be called via stub used for global calls. This issue can be fixed by teaching apply_relocate_add() to handle both SHN_UNDEF/SHN_LIVEPATCH symbols via the same stub. This patch extends SHN_UNDEF code to handle livepatch symbols too. Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Benjamin Herrenschmidt authored
This message isn't terribly useful. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Benjamin Herrenschmidt authored
This statement causes some not very useful messages to always be printed on the serial port at boot, even on quiet boots. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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- 04 Dec, 2017 7 commits
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Cyril Bur authored
Signed-off-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Gustavo Romero <gromero@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Santosh Sivaraj authored
Current vDSO64 implementation does not have support for coarse clocks (CLOCK_MONOTONIC_COARSE, CLOCK_REALTIME_COARSE), for which it falls back to system call, increasing the response time, vDSO implementation reduces the cycle time. Below is a benchmark of the difference in execution times. (Non-coarse clocks are also included just for completion) clock-gettime-realtime: syscall: 172 nsec/call clock-gettime-realtime: libc: 28 nsec/call clock-gettime-realtime: vdso: 22 nsec/call clock-gettime-monotonic: syscall: 171 nsec/call clock-gettime-monotonic: libc: 30 nsec/call clock-gettime-monotonic: vdso: 25 nsec/call clock-gettime-realtime-coarse: syscall: 153 nsec/call clock-gettime-realtime-coarse: libc: 16 nsec/call clock-gettime-realtime-coarse: vdso: 10 nsec/call clock-gettime-monotonic-coarse: syscall: 167 nsec/call clock-gettime-monotonic-coarse: libc: 17 nsec/call clock-gettime-monotonic-coarse: vdso: 11 nsec/call CC: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Santosh Sivaraj <santosh@fossix.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Bhaktipriya Shridhar authored
The workqueue "ps3av->wq" queues a single work item &ps3av->work and hence doesn't require ordering. It is involved in waking up ps3avd to do the video mode setting and hence it's not being used on a memory reclaim path. Hence, it has been converted to use system_wq. System workqueues have been able to handle high level of concurrency for a long time now and hence it's not required to have a singlethreaded workqueue just to gain concurrency. Unlike a dedicated per-cpu workqueue created with create_singlethread_workqueue(), system_wq allows multiple work items to overlap executions even on the same CPU; however, a per-cpu workqueue doesn't have any CPU locality or global ordering guarantee unless the target CPU is explicitly specified and thus the increase of local concurrency shouldn't make any difference. The work item has been flushed in ps3av_remove to ensure that there are no pending tasks while disconnecting the driver. Signed-off-by: Bhaktipriya Shridhar <bhaktipriya96@gmail.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Dmitry Torokhov authored
Instead of manually coding the loop with of_find_node_by_name(), let's switch to the standard macro for iterating over nodes with given name. Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> [mpe: Fix build failures due to typo in mpc832x_mds.c] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Dmitry Torokhov authored
We are not using result, so this simply results in a leaked refcount. Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Dmitry Torokhov authored
We need to call of_node_put() for device nodes obtained with of_find_node_by_name(). Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Joe Perches authored
At some point, pr_warning will be removed so all logging messages use a consistent <prefix>_warn style. Update arch/powerpc/ Miscellanea: o Coalesce formats o Realign arguments o Use %s, __func__ instead of embedded function names o Remove unnecessary line continuations Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Geoff Levand <geoff@infradead.org> [mpe: Rebase due to some %pOF changes.] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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- 03 Dec, 2017 1 commit
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Linus Torvalds authored
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