kernel.git/arch/s390, branch linux-4.19.y

s390/syscalls: Avoid creation of arch/arch/ directory

2024-12-05T09:59:30Z

[ Upstream commit 0708967e2d56e370231fd07defa0d69f9ad125e8 ] Building the kernel with ARCH=s390 creates a weird arch/arch/ directory. $ find arch/arch arch/arch arch/arch/s390 arch/arch/s390/include arch/arch/s390/include/generated arch/arch/s390/include/generated/asm arch/arch/s390/include/generated/uapi arch/arch/s390/include/generated/uapi/asm The root cause is 'targets' in arch/s390/kernel/syscalls/Makefile, where the relative path is incorrect. Strictly speaking, 'targets' was not necessary in the first place because this Makefile uses 'filechk' instead of 'if_changed'. However, this commit keeps it, as it will be useful when converting 'filechk' to 'if_changed' later. Fixes: 5c75824d915e ("s390/syscalls: add Makefile to generate system call header files") Signed-off-by: Masahiro Yamada Link: https://lore.kernel.org/r/20241111134603.2063226-1-masahiroy@kernel.org Signed-off-by: Heiko Carstens Signed-off-by: Sasha Levin

KVM: s390: gaccess: Check if guest address is in memslot

2024-11-08T15:19:21Z

[ Upstream commit e8061f06185be0a06a73760d6526b8b0feadfe52 ] Previously, access_guest_page() did not check whether the given guest address is inside of a memslot. This is not a problem, since kvm_write_guest_page/kvm_read_guest_page return -EFAULT in this case. However, -EFAULT is also returned when copy_to/from_user fails. When emulating a guest instruction, the address being outside a memslot usually means that an addressing exception should be injected into the guest. Failure in copy_to/from_user however indicates that something is wrong in userspace and hence should be handled there. To be able to distinguish these two cases, return PGM_ADDRESSING in access_guest_page() when the guest address is outside guest memory. In access_guest_real(), populate vcpu->arch.pgm.code such that kvm_s390_inject_prog_cond() can be used in the caller for injecting into the guest (if applicable). Since this adds a new return value to access_guest_page(), we need to make sure that other callers are not confused by the new positive return value. There are the following users of access_guest_page(): - access_guest_with_key() does the checking itself (in guest_range_to_gpas()), so this case should never happen. Even if, the handling is set up properly. - access_guest_real() just passes the return code to its callers, which are: - read_guest_real() - see below - write_guest_real() - see below There are the following users of read_guest_real(): - ar_translation() in gaccess.c which already returns PGM_* - setup_apcb10(), setup_apcb00(), setup_apcb11() in vsie.c which always return -EFAULT on read_guest_read() nonzero return - no change - shadow_crycb(), handle_stfle() always present this as validity, this could be handled better but doesn't change current behaviour - no change There are the following users of write_guest_real(): - kvm_s390_store_status_unloaded() always returns -EFAULT on write_guest_real() failure. Fixes: 2293897805c2 ("KVM: s390: add architecture compliant guest access functions") Cc: stable@vger.kernel.org Signed-off-by: Nico Boehr Reviewed-by: Heiko Carstens Link: https://lore.kernel.org/r/20240917151904.74314-2-nrb@linux.ibm.com Acked-by: Janosch Frank Signed-off-by: Heiko Carstens Signed-off-by: Sasha Levin

KVM: s390: gaccess: Cleanup access to guest pages

2024-11-08T15:19:21Z

[ Upstream commit bad13799e0305deb258372b7298a86be4c78aaba ] Introduce a helper function for guest frame access. Signed-off-by: Janis Schoetterl-Glausch Reviewed-by: Janosch Frank Reviewed-by: David Hildenbrand Reviewed-by: Claudio Imbrenda Message-Id: <20211126164549.7046-4-scgl@linux.ibm.com> Signed-off-by: Janosch Frank Stable-dep-of: e8061f06185b ("KVM: s390: gaccess: Check if guest address is in memslot") Signed-off-by: Sasha Levin

KVM: s390: gaccess: Refactor access address range check

2024-11-08T15:19:21Z

[ Upstream commit 7faa543df19bf62d4583a64d3902705747f2ad29 ] Do not round down the first address to the page boundary, just translate it normally, which gives the value we care about in the first place. Given this, translating a single address is just the special case of translating a range spanning a single page. Make the output optional, so the function can be used to just check a range. Signed-off-by: Janis Schoetterl-Glausch Reviewed-by: Janosch Frank Reviewed-by: Claudio Imbrenda Message-Id: <20211126164549.7046-3-scgl@linux.ibm.com> Signed-off-by: Janosch Frank Stable-dep-of: e8061f06185b ("KVM: s390: gaccess: Check if guest address is in memslot") Signed-off-by: Sasha Levin

KVM: s390: gaccess: Refactor gpa and length calculation

2024-11-08T15:19:21Z

[ Upstream commit 416e7f0c9d613bf84e182eba9547ae8f9f5bfa4c ] Improve readability by renaming the length variable and not calculating the offset manually. Signed-off-by: Janis Schoetterl-Glausch Reviewed-by: Janosch Frank Reviewed-by: David Hildenbrand Reviewed-by: Claudio Imbrenda Message-Id: <20211126164549.7046-2-scgl@linux.ibm.com> Signed-off-by: Janosch Frank Stable-dep-of: e8061f06185b ("KVM: s390: gaccess: Check if guest address is in memslot") Signed-off-by: Sasha Levin

KVM: s390: Change virtual to physical address access in diag 0x258 handler

2024-11-08T15:19:19Z

commit cad4b3d4ab1f062708fff33f44d246853f51e966 upstream. The parameters for the diag 0x258 are real addresses, not virtual, but KVM was using them as virtual addresses. This only happened to work, since the Linux kernel as a guest used to have a 1:1 mapping for physical vs virtual addresses. Fix KVM so that it correctly uses the addresses as real addresses. Cc: stable@vger.kernel.org Fixes: 8ae04b8f500b ("KVM: s390: Guest's memory access functions get access registers") Suggested-by: Vasily Gorbik Signed-off-by: Michael Mueller Signed-off-by: Nico Boehr Reviewed-by: Christian Borntraeger Reviewed-by: Heiko Carstens Link: https://lore.kernel.org/r/20240917151904.74314-3-nrb@linux.ibm.com Acked-by: Janosch Frank Signed-off-by: Heiko Carstens Signed-off-by: Greg Kroah-Hartman

s390/cpum_sf: Remove WARN_ON_ONCE statements

2024-11-08T15:19:16Z

[ Upstream commit b495e710157606889f2d8bdc62aebf2aa02f67a7 ] Remove WARN_ON_ONCE statements. These have not triggered in the past. Signed-off-by: Thomas Richter Acked-by: Sumanth Korikkar Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Alexander Gordeev Signed-off-by: Vasily Gorbik Signed-off-by: Sasha Levin

s390/mm: Add cond_resched() to cmm_alloc/free_pages()

2024-11-08T15:19:16Z

[ Upstream commit 131b8db78558120f58c5dc745ea9655f6b854162 ] Adding/removing large amount of pages at once to/from the CMM balloon can result in rcu_sched stalls or workqueue lockups, because of busy looping w/o cond_resched(). Prevent this by adding a cond_resched(). cmm_free_pages() holds a spin_lock while looping, so it cannot be added directly to the existing loop. Instead, introduce a wrapper function that operates on maximum 256 pages at once, and add it there. Signed-off-by: Gerald Schaefer Reviewed-by: Heiko Carstens Signed-off-by: Heiko Carstens Signed-off-by: Sasha Levin

s390/facility: Disable compile time optimization for decompressor code

2024-11-08T15:19:16Z

[ Upstream commit 0147addc4fb72a39448b8873d8acdf3a0f29aa65 ] Disable compile time optimizations of test_facility() for the decompressor. The decompressor should not contain any optimized code depending on the architecture level set the kernel image is compiled for to avoid unexpected operation exceptions. Add a __DECOMPRESSOR check to test_facility() to enforce that facilities are always checked during runtime for the decompressor. Reviewed-by: Sven Schnelle Signed-off-by: Heiko Carstens Signed-off-by: Sasha Levin

asm-generic: Move common compat types to asm-generic/compat.h

2024-07-18T09:39:31Z

commit fb3739759474d150a9927b920a80ea2afb4c2a51 upstream. While converting compat system call handlers to work on 32-bit architectures, I found a number of types used in those handlers that are identical between all architectures. Let's move all the identical ones into asm-generic/compat.h to avoid having to add even more identical definitions of those types. For unknown reasons, mips defines __compat_gid32_t, __compat_uid32_t and compat_caddr_t as signed, while all others have them unsigned. This seems to be a mistake, but I'm leaving it alone here. The other types all differ by size or alignment on at least on architecture. compat_aio_context_t is currently defined in linux/compat.h but also needed for compat_sys_io_getevents(), so let's move it into the same place. While we still have not decided whether the 32-bit time handling will always use the compat syscalls, or in which form, I think this is a useful cleanup that we can merge regardless. Reviewed-by: Christoph Hellwig Signed-off-by: Arnd Bergmann Cc: Frank Scheiner Signed-off-by: Greg Kroah-Hartman