Merge tag 'alpha-for-v7.4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/lindholm/alpha

Pull alpha updates from Magnus Lindholm:
"This completes Alpha's conversion to GENERIC_ENTRY and enabl

Merge tag 'alpha-for-v7.4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/lindholm/alpha

Pull alpha updates from Magnus Lindholm:
"This completes Alpha's conversion to GENERIC_ENTRY and enables a range
of kernel features through Kconfig updates, including UBSAN, gcov,
kmemleak, page-table checking, fast GUP and sparse IRQs.

It includes TLB and MMU context fixes prompted by glibc test-suite
failures, HugeTLB support for 64KB, 512KB and 4MB pages, and fixes for
poisoned-page faults and page-table checking.

Machine-check handling is improved on Tsunami platforms, with bounded
EV6 logout decoding, Clipper environmental event reporting and safer
firmware console-log scanning.

Other changes add self-extracting compressed kernels with support for
all kernel compression formats, Alpha-specific XZ tuning, perf
register and user-stack sampling, and Alpha support in the seccomp
selftests. The series also fixes user stack-pointer reporting and IRQ
entry ordering, adds 128-bit shift helpers, cleans up linker sections,
and updates Kconfig help"

* tag 'alpha-for-v7.4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/lindholm/alpha: (57 commits)
alpha: add bounded Clipper console-log scanning
alpha: decode Clipper environmental events
alpha: decode and acknowledge Tsunami system machine checks
alpha: bound EV6 logout decoding by the processor area
alpha: describe the Tsunami system machine check frame
alpha: move Tsunami machine check handling to err_tsunami.c
alpha: fill in pc for software event samples
alpha: add HAVE_PERF_REGS and HAVE_PERF_USER_STACK_DUMP support
alpha: use user_stack_pointer() in KSTK_ESP() and dump_elf_thread()
alpha: stop storing the user stack pointer in pt_regs
alpha: fix stale user_stack_pointer()
selftests/seccomp: add Alpha support to seccomp_bpf
alpha: do not skip TLB shootdown IPIs for kthread-borrowed mms
alpha: do not clear remote MMU contexts in migrate_flush_tlb_page()
alpha: invalidate the local context in flush_icache_user_page()
alpha: invalidate the local context in flush_tlb_mm()
alpha: fix the local TLB invalidate in the UP flush_tlb_page()
alpha: fix the local TLB invalidate in flush_tlb_page()
alpha: invalidate the local context in flush_tlb_page()
alpha: only use a targeted tbi() when the target mm is really current
...

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alpha: add self-extracting compressed kernel boot stub

Alpha only ever supported gzip for the kernel image, and did so in a way
out of step with every other architecture: aboot, the disk boot loader

alpha: add self-extracting compressed kernel boot stub

Alpha only ever supported gzip for the kernel image, and did so in a way
out of step with every other architecture: aboot, the disk boot loader,
decompresses vmlinux.gz itself with its own bundled inflate code, so
adding a compression format meant writing a new decompressor inside
aboot as well as in the kernel.

Build a proper self-extracting arch/alpha/boot/compressed/vmlinux
instead, modeled on parisc: a small ELF stub with the real, compressed
vmlinux linked in, which decompresses the kernel, relocates it into
place and jumps to its entry point. aboot needs no changes.

The stub has no sanitizer or coverage runtime and must run on any Alpha,
so it builds private copies of the arch/alpha/lib/ memory and division
routines it needs instead of linking lib.a, whose objects carry the
kernel's instrumentation and -mcpu=.

The build now emits arch/alpha/boot/vmlinuz rather than vmlinux.gz,
which was never a name aboot cared about and would be a lie for an ELF
stub: the bootpz path in the same directory still produces real gzip
data as vmlinux.nh.gz. Existing aboot.conf files name the image as it
was installed in /boot, so only the command that copies it out of the
build tree changes.

Unlike parisc and mips, the stub is linked at START_ADDR rather than at
a separate low address; see compressed/vmlinux.lds.S. It has no console
output, since bringing up the HWRPB console callbacks needs more than
the CRB dispatch the kernel proper does much later, so error() just
halts.

The legacy SRM netboot path (bootpz.c) is left alone: it has its own
boot protocol (PALcode reinitialization, self-populated ZERO_PGE,
build-time-computed image sizes) that does not fit this design without a
separate rewrite, and keeps using plain gzip via vmlinux.nh.gz.

Co-developed-by: Magnus Lindholm <linmag7@gmail.com>
Signed-off-by: Magnus Lindholm <linmag7@gmail.com>
Signed-off-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Magnus Lindholm <linmag7@gmail.com>
Tested-by: Magnus Lindholm <linmag7@gmail.com>
Link: https://lore.kernel.org/r/20261017-alpha-kernel-compression-v2-2-c71e6b08dc63@gmail.com
Signed-off-by: Magnus Lindholm <linmag7@gmail.com>

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