Always use 64-bit physical addresses for dump_avail[] in minidumps

As of r365978, minidumps include a copy of dump_avail[].  This is an
array of vm_paddr_t ranges.  libkvm walks the array assuming that
sizeof(vm_paddr_t) is equal to the platform "word size", but that's not
correct on some platforms.  For instance, i386 uses a 64-bit vm_paddr_t.

Fix the problem by always dumping 64-bit addresses.  On platforms where
vm_paddr_t is 32 bits wide, namely arm and mips (sometimes), translate
dump_avail[] to an array of uint64_t ranges.  With this change, libkvm
no longer needs to maintain a notion of the target word size, so get rid
of it.

This is a no-op on platforms where sizeof(vm_paddr_t) == 8.

Reviewed by:	alc, kib
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D27082

9 files changed, 12 insertions, 34 deletions

diff --git a/lib/libkvm/kvm_minidump_aarch64.c b/lib/libkvm/kvm_minidump_aarch64.c
index d962a3647b412..7fd4219fbf214 100644
--- a/lib/libkvm/kvm_minidump_aarch64.c
+++ b/lib/libkvm/kvm_minidump_aarch64.c
@@ -127,8 +127,7 @@ _aarch64_minidump_initvtop(kvm_t *kd)
 	sparse_off = off + aarch64_round_page(vmst->hdr.bitmapsize) +
 	    aarch64_round_page(vmst->hdr.pmapsize);
 	if (_kvm_pt_init(kd, vmst->hdr.dumpavailsize, dump_avail_off,
-	    vmst->hdr.bitmapsize, off, sparse_off, AARCH64_PAGE_SIZE,
-	    sizeof(uint64_t)) == -1) {
+	    vmst->hdr.bitmapsize, off, sparse_off, AARCH64_PAGE_SIZE) == -1) {
 		return (-1);
 	}
 	off += aarch64_round_page(vmst->hdr.bitmapsize);
diff --git a/lib/libkvm/kvm_minidump_amd64.c b/lib/libkvm/kvm_minidump_amd64.c
index 6d9086bce8c69..d69925e474461 100644
--- a/lib/libkvm/kvm_minidump_amd64.c
+++ b/lib/libkvm/kvm_minidump_amd64.c
@@ -169,8 +169,7 @@ _amd64_minidump_initvtop(kvm_t *kd)
 	sparse_off = off + amd64_round_page(vmst->hdr.bitmapsize) +
 	    amd64_round_page(vmst->hdr.pmapsize);
 	if (_kvm_pt_init(kd, vmst->hdr.dumpavailsize, dump_avail_off,
-	    vmst->hdr.bitmapsize, off, sparse_off, AMD64_PAGE_SIZE,
-	    sizeof(uint64_t)) == -1) {
+	    vmst->hdr.bitmapsize, off, sparse_off, AMD64_PAGE_SIZE) == -1) {
 		return (-1);
 	}
 	off += amd64_round_page(vmst->hdr.bitmapsize);
diff --git a/lib/libkvm/kvm_minidump_arm.c b/lib/libkvm/kvm_minidump_arm.c
index e76889c5eb8f0..82b83c10c7991 100644
--- a/lib/libkvm/kvm_minidump_arm.c
+++ b/lib/libkvm/kvm_minidump_arm.c
@@ -135,8 +135,7 @@ _arm_minidump_initvtop(kvm_t *kd)
 	sparse_off = off + arm_round_page(vmst->hdr.bitmapsize) +
 	    arm_round_page(vmst->hdr.ptesize);
 	if (_kvm_pt_init(kd, vmst->hdr.dumpavailsize, dump_avail_off,
-	    vmst->hdr.bitmapsize, off, sparse_off, ARM_PAGE_SIZE,
-	    sizeof(uint32_t)) == -1) {
+	    vmst->hdr.bitmapsize, off, sparse_off, ARM_PAGE_SIZE) == -1) {
 		return (-1);
 	}
 	off += arm_round_page(vmst->hdr.bitmapsize);
diff --git a/lib/libkvm/kvm_minidump_i386.c b/lib/libkvm/kvm_minidump_i386.c
index 8349c997bdc23..4f077ca1739a1 100644
--- a/lib/libkvm/kvm_minidump_i386.c
+++ b/lib/libkvm/kvm_minidump_i386.c
@@ -131,8 +131,7 @@ _i386_minidump_initvtop(kvm_t *kd)
 	sparse_off = off + i386_round_page(vmst->hdr.bitmapsize) +
 	    i386_round_page(vmst->hdr.ptesize);
 	if (_kvm_pt_init(kd, vmst->hdr.dumpavailsize, dump_avail_off,
-	    vmst->hdr.bitmapsize, off, sparse_off, I386_PAGE_SIZE,
-	    sizeof(uint32_t)) == -1) {
+	    vmst->hdr.bitmapsize, off, sparse_off, I386_PAGE_SIZE) == -1) {
 		return (-1);
 	}
 	off += i386_round_page(vmst->hdr.bitmapsize);
diff --git a/lib/libkvm/kvm_minidump_mips.c b/lib/libkvm/kvm_minidump_mips.c
index 4a0774733fc5f..dda6f35518723 100644
--- a/lib/libkvm/kvm_minidump_mips.c
+++ b/lib/libkvm/kvm_minidump_mips.c
@@ -136,8 +136,7 @@ _mips_minidump_initvtop(kvm_t *kd)
 	sparse_off = off + mips_round_page(vmst->hdr.bitmapsize) +
 	    mips_round_page(vmst->hdr.ptesize);
 	if (_kvm_pt_init(kd, vmst->hdr.dumpavailsize, dump_avail_off,
-	    vmst->hdr.bitmapsize, off, sparse_off, MIPS_PAGE_SIZE,
-	    sizeof(uint32_t)) == -1) {
+	    vmst->hdr.bitmapsize, off, sparse_off, MIPS_PAGE_SIZE) == -1) {
 		return (-1);
 	}
 	off += mips_round_page(vmst->hdr.bitmapsize);
diff --git a/lib/libkvm/kvm_minidump_powerpc64.c b/lib/libkvm/kvm_minidump_powerpc64.c
index 30ba967a06282..24def29a7c830 100644
--- a/lib/libkvm/kvm_minidump_powerpc64.c
+++ b/lib/libkvm/kvm_minidump_powerpc64.c
@@ -155,8 +155,7 @@ _powerpc64_minidump_initvtop(kvm_t *kd)
 
 	/* build physical address lookup table for sparse pages */
 	if (_kvm_pt_init(kd, hdr->dumpavailsize, dump_avail_off,
-	    hdr->bitmapsize, bitmap_off, sparse_off, PPC64_PAGE_SIZE,
-	    sizeof(uint64_t)) == -1)
+	    hdr->bitmapsize, bitmap_off, sparse_off, PPC64_PAGE_SIZE) == -1)
 		goto failed;
 
 	if (_kvm_pmap_init(kd, hdr->pmapsize, pmap_off) == -1)
diff --git a/lib/libkvm/kvm_minidump_riscv.c b/lib/libkvm/kvm_minidump_riscv.c
index 05d713d4b2213..4b825afe27d97 100644
--- a/lib/libkvm/kvm_minidump_riscv.c
+++ b/lib/libkvm/kvm_minidump_riscv.c
@@ -128,8 +128,7 @@ _riscv_minidump_initvtop(kvm_t *kd)
 	sparse_off = off + riscv_round_page(vmst->hdr.bitmapsize) +
 	    riscv_round_page(vmst->hdr.pmapsize);
 	if (_kvm_pt_init(kd, vmst->hdr.dumpavailsize, dump_avail_off,
-	    vmst->hdr.bitmapsize, off, sparse_off, RISCV_PAGE_SIZE,
-	    sizeof(uint64_t)) == -1) {
+	    vmst->hdr.bitmapsize, off, sparse_off, RISCV_PAGE_SIZE) == -1) {
 		return (-1);
 	}
 	off += riscv_round_page(vmst->hdr.bitmapsize);
diff --git a/lib/libkvm/kvm_private.c b/lib/libkvm/kvm_private.c
index 9424502adfad5..d853d16431018 100644
--- a/lib/libkvm/kvm_private.c
+++ b/lib/libkvm/kvm_private.c
@@ -291,8 +291,7 @@ _kvm_map_get(kvm_t *kd, u_long pa, unsigned int page_size)
 
 int
 _kvm_pt_init(kvm_t *kd, size_t dump_avail_size, off_t dump_avail_off,
-    size_t map_len, off_t map_off, off_t sparse_off, int page_size,
-    int word_size)
+    size_t map_len, off_t map_off, off_t sparse_off, int page_size)
 {
 	uint64_t *addr;
 	uint32_t *popcount_bin;
@@ -311,14 +310,8 @@ _kvm_pt_init(kvm_t *kd, size_t dump_avail_size, off_t dump_avail_off,
 		 * last_pa. Create an implied dump_avail that
 		 * expresses this.
 		 */
-		kd->dump_avail = calloc(4, word_size);
-		if (word_size == sizeof(uint32_t)) {
-			((uint32_t *)kd->dump_avail)[1] = _kvm32toh(kd,
-			    map_len * 8 * page_size);
-		} else {
-			kd->dump_avail[1] = _kvm64toh(kd,
-			    map_len * 8 * page_size);
-		}
+		kd->dump_avail = calloc(4, sizeof(uint64_t));
+		kd->dump_avail[1] = _kvm64toh(kd, map_len * 8 * page_size);
 	}
 
 	/*
@@ -375,7 +368,6 @@ _kvm_pt_init(kvm_t *kd, size_t dump_avail_size, off_t dump_avail_off,
 	kd->pt_sparse_off = sparse_off;
 	kd->pt_sparse_size = (uint64_t)*popcount_bin * page_size;
 	kd->pt_page_size = page_size;
-	kd->pt_word_size = word_size;
 
 	/*
 	 * Map the sparse page array.  This is useful for performing point
@@ -419,13 +411,7 @@ _kvm_pmap_init(kvm_t *kd, uint32_t pmap_size, off_t pmap_off)
 static inline uint64_t
 dump_avail_n(kvm_t *kd, long i)
 {
-	uint32_t *d32;
-
-	if (kd->pt_word_size == sizeof(uint32_t)) {
-		d32 = (uint32_t *)kd->dump_avail;
-		return (_kvm32toh(kd, d32[i]));
-	} else
-		return (_kvm64toh(kd, kd->dump_avail[i]));
+	return (_kvm64toh(kd, kd->dump_avail[i]));
 }
 
 uint64_t
diff --git a/lib/libkvm/kvm_private.h b/lib/libkvm/kvm_private.h
index 5a8ea524d0a90..d4ec1ff1837b3 100644
--- a/lib/libkvm/kvm_private.h
+++ b/lib/libkvm/kvm_private.h
@@ -112,7 +112,6 @@ struct __kvm {
 	uint64_t	pt_sparse_size;
 	uint32_t	*pt_popcounts;
 	unsigned int	pt_page_size;
-	unsigned int	pt_word_size;
 
 	/* Page & sparse map structures. */
 	void		*page_map;
@@ -190,7 +189,7 @@ kvaddr_t _kvm_dpcpu_validaddr(kvm_t *, kvaddr_t);
 int	 _kvm_probe_elf_kernel(kvm_t *, int, int);
 int	 _kvm_is_minidump(kvm_t *);
 int	 _kvm_read_core_phdrs(kvm_t *, size_t *, GElf_Phdr **);
-int	 _kvm_pt_init(kvm_t *, size_t, off_t, size_t, off_t, off_t, int, int);
+int	 _kvm_pt_init(kvm_t *, size_t, off_t, size_t, off_t, off_t, int);
 off_t	 _kvm_pt_find(kvm_t *, uint64_t, unsigned int);
 int	 _kvm_visit_cb(kvm_t *, kvm_walk_pages_cb_t *, void *, u_long,
 	    u_long, u_long, vm_prot_t, size_t, unsigned int);