kernel/linux.git, branch v3.14.23

Linux 3.14.23

2014-10-30T16:38:45+00:00

sparc64: Implement __get_user_pages_fast().

2014-10-30T16:38:28+00:00

[ Upstream commit 06090e8ed89ea2113a236befb41f71d51f100e60 ] It is not sufficient to only implement get_user_pages_fast(), you must also implement the atomic version __get_user_pages_fast() otherwise you end up using the weak symbol fallback implementation which simply returns zero. This is dangerous, because it causes the futex code to loop forever if transparent hugepages are supported (see get_futex_key()). Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sparc64: Fix register corruption in top-most kernel stack frame during boot.

2014-10-30T16:38:28+00:00

[ Upstream commit ef3e035c3a9b81da8a778bc333d10637acf6c199 ] Meelis Roos reported that kernels built with gcc-4.9 do not boot, we eventually narrowed this down to only impacting machines using UltraSPARC-III and derivitive cpus. The crash happens right when the first user process is spawned: [ 54.451346] Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000004 [ 54.451346] [ 54.571516] CPU: 1 PID: 1 Comm: init Not tainted 3.16.0-rc2-00211-gd7933ab #96 [ 54.666431] Call Trace: [ 54.698453] [0000000000762f8c] panic+0xb0/0x224 [ 54.759071] [000000000045cf68] do_exit+0x948/0x960 [ 54.823123] [000000000042cbc0] fault_in_user_windows+0xe0/0x100 [ 54.902036] [0000000000404ad0] __handle_user_windows+0x0/0x10 [ 54.978662] Press Stop-A (L1-A) to return to the boot prom [ 55.050713] ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000004 Further investigation showed that compiling only per_cpu_patch() with an older compiler fixes the boot. Detailed analysis showed that the function is not being miscompiled by gcc-4.9, but it is using a different register allocation ordering. With the gcc-4.9 compiled function, something during the code patching causes some of the %i* input registers to get corrupted. Perhaps we have a TLB miss path into the firmware that is deep enough to cause a register window spill and subsequent restore when we get back from the TLB miss trap. Let's plug this up by doing two things: 1) Stop using the firmware stack for client interface calls into the firmware. Just use the kernel's stack. 2) As soon as we can, call into a new function "start_early_boot()" to put a one-register-window buffer between the firmware's deepest stack frame and the top-most initial kernel one. Reported-by: Meelis Roos Tested-by: Meelis Roos Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sparc64: Increase size of boot string to 1024 bytes

2014-10-30T16:38:28+00:00

[ Upstream commit 1cef94c36bd4d79b5ae3a3df99ee0d76d6a4a6dc ] This is the longest boot string that silo supports. Signed-off-by: Dave Kleikamp Cc: Bob Picco Cc: David S. Miller Cc: sparclinux@vger.kernel.org Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sparc64: Kill unnecessary tables and increase MAX_BANKS.

2014-10-30T16:38:28+00:00

[ Upstream commit d195b71bad4347d2df51072a537f922546a904f1 ] swapper_low_pmd_dir and swapper_pud_dir are actually completely useless and unnecessary. We just need swapper_pg_dir[]. Naturally the other page table chunks will be allocated on an as-needed basis. Since the kernel actually accesses these tables in the PAGE_OFFSET view, there is not even a TLB locality advantage of placing them in the kernel image. Use the hard coded vmlinux.ld.S slot for swapper_pg_dir which is naturally page aligned. Increase MAX_BANKS to 1024 in order to handle heavily fragmented virtual guests. Even with this MAX_BANKS increase, the kernel is 20K+ smaller. Signed-off-by: David S. Miller Acked-by: Bob Picco Signed-off-by: Greg Kroah-Hartman

sparc64: sparse irq

2014-10-30T16:38:27+00:00

[ Upstream commit ee6a9333fa58e11577c1b531b8e0f5ffc0fd6f50 ] This patch attempts to do a few things. The highlights are: 1) enable SPARSE_IRQ unconditionally, 2) kills off !SPARSE_IRQ code 3) allocates ivector_table at boot time and 4) default to cookie only VIRQ mechanism for supported firmware. The first firmware with cookie only support for me appears on T5. You can optionally force the HV firmware to not cookie only mode which is the sysino support. The sysino is a deprecated HV mechanism according to the most recent SPARC Virtual Machine Specification. HV_GRP_INTR is what controls the cookie/sysino firmware versioning. The history of this interface is: 1) Major version 1.0 only supported sysino based interrupt interfaces. 2) Major version 2.0 added cookie based VIRQs, however due to the fact that OSs were using the VIRQs without negoatiating major version 2.0 (Linux and Solaris are both guilty), the VIRQs calls were allowed even with major version 1.0 To complicate things even further, the VIRQ interfaces were only actually hooked up in the hypervisor for LDC interrupt sources. VIRQ calls on other device types would result in HV_EINVAL errors. So effectively, major version 2.0 is unusable. 3) Major version 3.0 was created to signal use of VIRQs and the fact that the hypervisor has these calls hooked up for all interrupt sources, not just those for LDC devices. A new boot option is provided should cookie only HV support have issues. hvirq - this is the version for HV_GRP_INTR. This is related to HV API versioning. The code attempts major=3 first by default. The option can be used to override this default. I've tested with SPARSE_IRQ on T5-8, M7-4 and T4-X and Jalap?no. Signed-off-by: Bob Picco Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sparc64: Adjust vmalloc region size based upon available virtual address bits.

2014-10-30T16:38:27+00:00

[ Upstream commit bb4e6e85daa52a9f6210fa06a5ec6269598a202b ] In order to accomodate embedded per-cpu allocation with large numbers of cpus and numa nodes, we have to use as much virtual address space as possible for the vmalloc region. Otherwise we can get things like: PERCPU: max_distance=0x380001c10000 too large for vmalloc space 0xff00000000 So, once we select a value for PAGE_OFFSET, derive the size of the vmalloc region based upon that. Signed-off-by: David S. Miller Acked-by: Bob Picco Signed-off-by: Greg Kroah-Hartman

sparc64: Increase MAX_PHYS_ADDRESS_BITS to 53.

2014-10-30T16:38:27+00:00

Make sure, at compile time, that the kernel can properly support whatever MAX_PHYS_ADDRESS_BITS is defined to. On M7 chips, use a max_phys_bits value of 49. Based upon a patch by Bob Picco. Signed-off-by: David S. Miller Acked-by: Bob Picco Signed-off-by: Greg Kroah-Hartman

sparc64: Use kernel page tables for vmemmap.

2014-10-30T16:38:27+00:00

[ Upstream commit c06240c7f5c39c83dfd7849c0770775562441b96 ] For sparse memory configurations, the vmemmap array behaves terribly and it takes up an inordinate amount of space in the BSS section of the kernel image unconditionally. Just build huge PMDs and look them up just like we do for TLB misses in the vmalloc area. Kernel BSS shrinks by about 2MB. Signed-off-by: David S. Miller Acked-by: Bob Picco Signed-off-by: Greg Kroah-Hartman

sparc64: Fix physical memory management regressions with large max_phys_bits.

2014-10-30T16:38:27+00:00

[ Upstream commit 0dd5b7b09e13dae32869371e08e1048349fd040c ] If max_phys_bits needs to be > 43 (f.e. for T4 chips), things like DEBUG_PAGEALLOC stop working because the 3-level page tables only can cover up to 43 bits. Another problem is that when we increased MAX_PHYS_ADDRESS_BITS up to 47, several statically allocated tables became enormous. Compounding this is that we will need to support up to 49 bits of physical addressing for M7 chips. The two tables in question are sparc64_valid_addr_bitmap and kpte_linear_bitmap. The first holds a bitmap, with 1 bit for each 4MB chunk of physical memory, indicating whether that chunk actually exists in the machine and is valid. The second table is a set of 2-bit values which tell how large of a mapping (4MB, 256MB, 2GB, 16GB, respectively) we can use at each 256MB chunk of ram in the system. These tables are huge and take up an enormous amount of the BSS section of the sparc64 kernel image. Specifically, the sparc64_valid_addr_bitmap is 4MB, and the kpte_linear_bitmap is 128K. So let's solve the space wastage and the DEBUG_PAGEALLOC problem at the same time, by using the kernel page tables (as designed) to manage this information. We have to keep using large mappings when DEBUG_PAGEALLOC is disabled, and we do this by encoding huge PMDs and PUDs. On a T4-2 with 256GB of ram the kernel page table takes up 16K with DEBUG_PAGEALLOC disabled and 256MB with it enabled. Furthermore, this memory is dynamically allocated at run time rather than coded statically into the kernel image. Signed-off-by: David S. Miller Acked-by: Bob Picco Signed-off-by: Greg Kroah-Hartman