Merge branch 'parisc-4.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux

Pull parisc updates from Helge Deller:
 "Main changes are:

   - Added support to the parisc dma functions to return DMA_ERROR_CODE
     if DMA isn't possible. This fixes a long standing kernel crash if
     parport_pc is enabled (by Thomas Bogendoerfer, marked for stable
     series).

   - Use the compat_sys_keyctl() in compat mode (by Eric Biggers, marked
     for stable series).

   - Initial support for the Page Deallocation Table (PDT) which is
     maintained by firmware and holds the list of memory addresses which
     had physical errors. By checking that list we can prevent Linux to
     use those broken memory areas.

   - Ensure IRQs are off in switch_mm().

   - Report SIGSEGV instead of SIGBUS when running out of stack.

   - Mark the cr16 clocksource stable on single-socket and single-core
     machines"

* 'parisc-4.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: DMA API: return error instead of BUG_ON for dma ops on non dma devs
  parisc: Report SIGSEGV instead of SIGBUS when running out of stack
  parisc: use compat_sys_keyctl()
  parisc: Don't hardcode PSW values in hpmc code
  parisc: Don't hardcode PSW values in gsc_*() functions
  parisc: Avoid zeroing gr[0] in fixup_exception()
  parisc/mm: Ensure IRQs are off in switch_mm()
  parisc: Add Page Deallocation Table (PDT) support
  parisc: Enhance detection of synchronous cr16 clocksources
  parisc: Drop per_cpu uaccess related exception_data struct
  parisc: Inline trivial exception code in lusercopy.S

1 files changed, 143 insertions, 0 deletions

diff --git a/arch/parisc/kernel/pdt.c b/arch/parisc/kernel/pdt.c
new file mode 100644
index 000000000000..f3a797e670b0
--- /dev/null
+++ b/arch/parisc/kernel/pdt.c
@@ -0,0 +1,143 @@
+/*
+ *    Page Deallocation Table (PDT) support
+ *
+ *    The Page Deallocation Table (PDT) holds a table with pointers to bad
+ *    memory (broken RAM modules) which is maintained by firmware.
+ *
+ *    Copyright 2017 by Helge Deller <deller@gmx.de>
+ *
+ *    TODO:
+ *    - check regularily for new bad memory
+ *    - add userspace interface with procfs or sysfs
+ *    - increase number of PDT entries dynamically
+ */
+
+#include <linux/memblock.h>
+#include <linux/seq_file.h>
+
+#include <asm/pdc.h>
+#include <asm/pdcpat.h>
+#include <asm/sections.h>
+#include <asm/pgtable.h>
+
+enum pdt_access_type {
+	PDT_NONE,
+	PDT_PDC,
+	PDT_PAT_NEW,
+	PDT_PAT_OLD
+};
+
+static enum pdt_access_type pdt_type;
+
+/* global PDT status information */
+static struct pdc_mem_retinfo pdt_status;
+
+#define MAX_PDT_TABLE_SIZE	PAGE_SIZE
+#define MAX_PDT_ENTRIES		(MAX_PDT_TABLE_SIZE / sizeof(unsigned long))
+static unsigned long pdt_entry[MAX_PDT_ENTRIES] __page_aligned_bss;
+
+
+/* report PDT entries via /proc/meminfo */
+void arch_report_meminfo(struct seq_file *m)
+{
+	if (pdt_type == PDT_NONE)
+		return;
+
+	seq_printf(m, "PDT_max_entries: %7lu\n",
+			pdt_status.pdt_size);
+	seq_printf(m, "PDT_cur_entries: %7lu\n",
+			pdt_status.pdt_entries);
+}
+
+/*
+ * pdc_pdt_init()
+ *
+ * Initialize kernel PDT structures, read initial PDT table from firmware,
+ * report all current PDT entries and mark bad memory with memblock_reserve()
+ * to avoid that the kernel will use broken memory areas.
+ *
+ */
+void __init pdc_pdt_init(void)
+{
+	int ret, i;
+	unsigned long entries;
+	struct pdc_mem_read_pdt pdt_read_ret;
+
+	if (is_pdc_pat()) {
+		struct pdc_pat_mem_retinfo pat_rinfo;
+
+		pdt_type = PDT_PAT_NEW;
+		ret = pdc_pat_mem_pdt_info(&pat_rinfo);
+		pdt_status.pdt_size = pat_rinfo.max_pdt_entries;
+		pdt_status.pdt_entries = pat_rinfo.current_pdt_entries;
+		pdt_status.pdt_status = 0;
+		pdt_status.first_dbe_loc = pat_rinfo.first_dbe_loc;
+		pdt_status.good_mem = pat_rinfo.good_mem;
+	} else {
+		pdt_type = PDT_PDC;
+		ret = pdc_mem_pdt_info(&pdt_status);
+	}
+
+	if (ret != PDC_OK) {
+		pdt_type = PDT_NONE;
+		pr_info("PDT: Firmware does not provide any page deallocation"
+			" information.\n");
+		return;
+	}
+
+	entries = pdt_status.pdt_entries;
+	WARN_ON(entries > MAX_PDT_ENTRIES);
+
+	pr_info("PDT: size %lu, entries %lu, status %lu, dbe_loc 0x%lx,"
+		" good_mem %lu\n",
+			pdt_status.pdt_size, pdt_status.pdt_entries,
+			pdt_status.pdt_status, pdt_status.first_dbe_loc,
+			pdt_status.good_mem);
+
+	if (entries == 0) {
+		pr_info("PDT: Firmware reports all memory OK.\n");
+		return;
+	}
+
+	if (pdt_status.first_dbe_loc &&
+		pdt_status.first_dbe_loc <= __pa((unsigned long)&_end))
+		pr_crit("CRITICAL: Bad memory inside kernel image memory area!\n");
+
+	pr_warn("PDT: Firmware reports %lu entries of faulty memory:\n",
+		entries);
+
+	if (pdt_type == PDT_PDC)
+		ret = pdc_mem_pdt_read_entries(&pdt_read_ret, pdt_entry);
+	else {
+#ifdef CONFIG_64BIT
+		struct pdc_pat_mem_read_pd_retinfo pat_pret;
+
+		ret = pdc_pat_mem_read_cell_pdt(&pat_pret, pdt_entry,
+			MAX_PDT_ENTRIES);
+		if (ret != PDC_OK) {
+			pdt_type = PDT_PAT_OLD;
+			ret = pdc_pat_mem_read_pd_pdt(&pat_pret, pdt_entry,
+				MAX_PDT_TABLE_SIZE, 0);
+		}
+#else
+		ret = PDC_BAD_PROC;
+#endif
+	}
+
+	if (ret != PDC_OK) {
+		pdt_type = PDT_NONE;
+		pr_debug("PDT type %d, retval = %d\n", pdt_type, ret);
+		return;
+	}
+
+	for (i = 0; i < pdt_status.pdt_entries; i++) {
+		if (i < 20)
+			pr_warn("PDT: BAD PAGE #%d at 0x%08lx (error_type = %lu)\n",
+				i,
+				pdt_entry[i] & PAGE_MASK,
+				pdt_entry[i] & 1);
+
+		/* mark memory page bad */
+		memblock_reserve(pdt_entry[i] & PAGE_MASK, PAGE_SIZE);
+	}
+}