kernel.git/arch/s390/include/asm/pgtable.h, branch linux-5.13.y

s390: enable HAVE_IOREMAP_PROT

2021-07-14T15:07:35Z

[ Upstream commit d460bb6c6417588dd8b0907d34f69b237918812a ] In commit b02002cc4c0f ("s390/pci: Implement ioremap_wc/prot() with MIO") we implemented both ioremap_wc() and ioremap_prot() however until now we had not set HAVE_IOREMAP_PROT in Kconfig, do so now. This also requires implementing pte_pgprot() as this is used in the generic_access_phys() code enabled by CONFIG_HAVE_IOREMAP_PROT. As with ioremap_wc() we need to take the MMIO Write Back bit index into account. Moreover since the pgprot value returned from pte_pgprot() is to be used for mappings into kernel address space we must make sure that it uses appropriate kernel page table protection bits. In particular a pgprot value originally coming from userspace could have the _PAGE_PROTECT bit set to enable fault based dirty bit accounting which would then make the mapping inaccessible when used in kernel address space. Fixes: b02002cc4c0f ("s390/pci: Implement ioremap_wc/prot() with MIO") Reviewed-by: Gerald Schaefer Signed-off-by: Niklas Schnelle Signed-off-by: Vasily Gorbik Signed-off-by: Sasha Levin

mm: define default MAX_PTRS_PER_* in include/pgtable.h

2021-07-14T15:06:38Z

[ Upstream commit c0f8aa4fa815daacb6eca52cae04820d6aecb7c2 ] Commit c65e774fb3f6 ("x86/mm: Make PGDIR_SHIFT and PTRS_PER_P4D variable") made PTRS_PER_P4D variable on x86 and introduced MAX_PTRS_PER_P4D as a constant for cases which need a compile-time constant (e.g. fixed-size arrays). powerpc likewise has boot-time selectable MMU features which can cause other mm "constants" to vary. For KASAN, we have some static PTE/PMD/PUD/P4D arrays so we need compile-time maximums for all these constants. Extend the MAX_PTRS_PER_ idiom, and place default definitions in include/pgtable.h. These define MAX_PTRS_PER_x to be PTRS_PER_x unless an architecture has defined MAX_PTRS_PER_x in its arch headers. Clean up pgtable-nop4d.h and s390's MAX_PTRS_PER_P4D definitions while we're at it: both can just pick up the default now. Link: https://lkml.kernel.org/r/20210624034050.511391-4-dja@axtens.net Signed-off-by: Daniel Axtens Acked-by: Andrey Konovalov Reviewed-by: Christophe Leroy Reviewed-by: Marco Elver Cc: Aneesh Kumar K.V Cc: Balbir Singh Cc: Alexander Potapenko Cc: Andrey Ryabinin Cc: Dmitry Vyukov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

s390/mm: fix invalid __pa() usage in pfn_pXd() macros

2021-02-23T23:31:22Z

There is little sense in applying __pa() to a physical address, but that what pfn_pXd() macros do. Signed-off-by: Alexander Gordeev Reviewed-by: Heiko Carstens Signed-off-by: Vasily Gorbik

s390/mm: make pXd_deref() macros return a pointer

2021-02-23T23:31:22Z

This update fixes semantics of pXd_deref macros which are expected to return a CPU-addressable pointer. Signed-off-by: Alexander Gordeev Reviewed-by: Heiko Carstens Signed-off-by: Vasily Gorbik

s390/mm: use invalid asce instead of kernel asce

2020-11-23T11:01:12Z

Create a region 3 page table which contains only invalid entries, and use that via "s390_invalid_asce" instead of the kernel ASCE whenever there is either - no user address space available, e.g. during early startup - as an intermediate ASCE when address spaces are switched This makes sure that user space accesses in such situations are guaranteed to fail. Reviewed-by: Sven Schnelle Reviewed-by: Alexander Gordeev Signed-off-by: Heiko Carstens

s390/mm: extend default vmalloc area size to 512GB

2020-11-09T10:20:59Z

We've seen several occurences in the past where the default vmalloc size of 128GB is not sufficient. Therefore extend the default size. Reviewed-by: Claudio Imbrenda Reviewed-by: Vasily Gorbik Signed-off-by: Heiko Carstens

s390/mm: make pmd/pud_deref() large page aware

2020-11-03T14:12:15Z

pmd/pud_deref() assume that they will never operate on large pmd/pud entries, and therefore only use the non-large _xxx_ENTRY_ORIGIN mask. With commit 9ec8fa8dc331b ("s390/vmemmap: extend modify_pagetable() to handle vmemmap"), that assumption is no longer true, at least for pmd_deref(). In theory, we could end up with wrong addresses because some of the non-address bits of a large entry would not be masked out. In practice, this does not (yet) show any impact, because vmemmap_free() is currently never used for s390. Fix pmd/pud_deref() to check for the entry type and use the _xxx_ENTRY_ORIGIN_LARGE mask for large entries. While at it, also move pmd/pud_pfn() around, in order to avoid code duplication, because they do the same thing. Fixes: 9ec8fa8dc331b ("s390/vmemmap: extend modify_pagetable() to handle vmemmap") Cc: # 5.9 Signed-off-by: Gerald Schaefer Reviewed-by: Alexander Gordeev Signed-off-by: Heiko Carstens

Merge tag 's390-5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

2020-10-16T19:36:38Z

Pull s390 updates from Vasily Gorbik: - Remove address space overrides using set_fs() - Convert to generic vDSO - Convert to generic page table dumper - Add ARCH_HAS_DEBUG_WX support - Add leap seconds handling support - Add NVMe firmware-assisted kernel dump support - Extend NVMe boot support with memory clearing control and addition of kernel parameters - AP bus and zcrypt api code rework. Add adapter configure/deconfigure interface. Extend debug features. Add failure injection support - Add ECC secure private keys support - Add KASan support for running protected virtualization host with 4-level paging - Utilize destroy page ultravisor call to speed up secure guests shutdown - Implement ioremap_wc() and ioremap_prot() with MIO in PCI code - Various checksum improvements - Other small various fixes and improvements all over the code * tag 's390-5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (85 commits) s390/uaccess: fix indentation s390/uaccess: add default cases for __put_user_fn()/__get_user_fn() s390/zcrypt: fix wrong format specifications s390/kprobes: move insn_page to text segment s390/sie: fix typo in SIGP code description s390/lib: fix kernel doc for memcmp() s390/zcrypt: Introduce Failure Injection feature s390/zcrypt: move ap_msg param one level up the call chain s390/ap/zcrypt: revisit ap and zcrypt error handling s390/ap: Support AP card SCLP config and deconfig operations s390/sclp: Add support for SCLP AP adapter config/deconfig s390/ap: add card/queue deconfig state s390/ap: add error response code field for ap queue devices s390/ap: split ap queue state machine state from device state s390/zcrypt: New config switch CONFIG_ZCRYPT_DEBUG s390/zcrypt: introduce msg tracking in zcrypt functions s390/startup: correct early pgm check info formatting s390: remove orphaned extern variables declarations s390/kasan: make sure int handler always run with DAT on s390/ipl: add support to control memory clearing for nvme re-IPL ...

mm/gup: fix gup_fast with dynamic page table folding

2020-09-26T17:33:57Z

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 Signed-off-by: Andrew Morton Reviewed-by: Gerald Schaefer Reviewed-by: Alexander Gordeev Reviewed-by: Jason Gunthorpe Reviewed-by: Mike Rapoport Reviewed-by: John Hubbard Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Dave Hansen Cc: Russell King Cc: Catalin Marinas Cc: Will Deacon Cc: Michael Ellerman Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Jeff Dike Cc: Richard Weinberger Cc: Dave Hansen Cc: Andy Lutomirski Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: Arnd Bergmann Cc: Andrey Ryabinin Cc: Heiko Carstens Cc: Christian Borntraeger Cc: Claudio Imbrenda Cc: [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

s390/mm,ptdump: add couple of additional markers

2020-09-14T09:38:35Z

Signed-off-by: Vasily Gorbik [hca@linux.ibm.com: add more markers, rename some markers] Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik